Why isn't the resonance frequency of a vibration the damped frequency?

How do you define the resonance frequency of a forced damped oscillator?


Non-stationary charge distribution in quantum mechanics

Is there such a thing as charge density in quantum mechanics?


Is the definition of the meter arbitrary?


If virtual particles violate for a little moment the conservation of energy, can energy be created?

Why don't virtual particles violate conservation of mass/energy?


Colors sensitivity by human eye and light wavelength

Why does adding red light with blue light give purple light?


why galaxies look like discs rather than spheres?

Why are our planets in the solar system all on the same disc/plane/layer?


Does the coefficient of Kinetic Friction change depending on how fast you are moving?

Does kinetic friction increase as speed increases?


Special theory of relativity - relative movement

If I am travelling on a car at around 60 km/h, and I shine a light, does that mean that the light is travelling faster than the speed of light?


Why is the charge on protons == to charge on electrons?

Why do electron and proton have the same but opposite electric charge?


Why applying a force to something does not always result in an energy consumption?

If an object rests on a table, not accelerating, how much work do both the object and the table do?


Finding the generators of the adjoint representation

Solving the Lie algebra of generators: path from algebra to matrix representation


how do compression and expansion of air transfer energy(sound) and why it is adiabatic not isothermal?


Could the phase factor $i$ be replaced by "matrix representation" totally in quantum mechanics?

About the complex nature of the wave function?


Why is a nuclei with too many neutrons unstable?

Adding many more neutrons to a nucleus decreases stability?


how does the temperature of a gas increase when compressed by an external agent during sound production?


Why doesn't everything expand when the universe expands?

Why does space expansion not expand matter?


Question of size in double slit experiment


Thermodynamics, temperature below 0 Kelvin

Prove that negative absolute temperatures are actually hotter than positive absolute temperatures


Why does a floating balloon in an accelerated train moves forward but the pendulum moves backward?

Why does a helium filled balloon move forward in a car when the car is accelerating?


If I run along the aisle of a bus traveling at (almost) the speed of light, can I travel faster than the speed of light?


How to prove Gauss's law div(E) = rho/epsilon from Coulomb's law?

How is Gauss' Law (integral form) arrived at from Coulomb's Law, and how is the differential form arrived at from that?


Time taken for object in space to fall to earth


Could a super conductor actually be used to repel gravity?


Does Stephen Hawking believe that General Relativity is wrong?

Why does Stephen Hawking say black holes don't exist?


Can a gravitational field be diluted or shielded?

Is it theoretically possible to shield gravitational fields or waves?


Would particles in this container go over light speed?


Is plasma an intermediate stage of matter?

What's the difference between gas and plasma?


when an object is lifted (at a constant velocity) shouldn't the work done on the object be zero?


Effect of Eath's rotation on a ball thrown upwards

Earth moves how much under my feet when I jump?


What Happens When A Gravitational Wave Interacts With Another One?


Does timbre consist in pitch and volume?


If a mass moves close to the speed of light, does it turn into a black hole?


Can universe or anything be simulated with absolute accuracy?

Is the universe fundamentally deterministic?


Why don't metals bond when touched together?


How can a rotating cylinder produce lift?

By what mechanism is lift produced on a rotating cylinder in an inviscid flow?


2s orbital wavefunction has non-zero probability at $r=0$?

Hydrogen radial wave function infinity at $r=0$


How fast does the force of pulling a straight rope propagate along the rope?

What "propagates" a force through the rest of a solid?


Energy-level choice for electron at photon emission

Do we really not know why atoms 'decide' to produce a photon?


Do eyeballs exhibit chromatic aberration?


Why are the neutron and proton masses nearly equal?

What's with the very slightly larger mass of the neutron compared to the proton?


Is it possible to reach outer space with this method?

How much thrust would be needed to turn a hobbyist weather balloon into a deep space probe?


An error in my understanding of entanglement

The choice of measurement basis on one half of an entangled state affects the other half. Can this be used to communicate faster than light?


Formation of the event horizon seems impossible with singularity inside seems impossible

How can anything ever fall into a black hole as seen from an outside observer?


Was the expansion after the big bang faster than the speed of light?


Why does light bend towards the normal when passing from a rarer to a denser medium?


If a bullet is fired vertically upwards, when it comes back does it fall to the same spot?

Earth moves how much under my feet when I jump?


Is the size of the universe directly related to its temperature?

When they say that the universe cooled after the big bang, where did the heat go?


How did Newton find out gravity is proportional to the product of two masses?

Why in Newton's law of gravity, we do $M_1 \times M_2$ and not $M_1 + M_2$?


Can we derive most fundamental laws from the Action Principle?

How general is the Lagrangian quantization approach to field theory?


How can we see objects that are so far away?

Photons from stars--how do they fill in such large angular distances?


Should it be obvious that independent quantum states are composed by taking the tensor product?


Why do wave functions need to be normalized? Why aren't the normalized to begin with?

Who is doing the normalization of wave function in the time evolution of wave function?


How to explain the motion of these pendulums?


Calculating acceleration offset by Center of Gravity (C.G.)


Dipole moment of a displaced charge distribution

Radially symmetric charge distribution (dipole moment)


Do particles ever touch each other during a collision?


The exchange of photons gives rise to the electromagnetic force


How do you start learning physics by yourself?


Can a hovering helicopter travel half the globe in 12 hours?


a question of optical interference and it's energy propagation

What happens to the energy when waves perfectly cancel each other?


Why does holding something up cost energy while no work is being done?


Experimental proof of gravity propagation?

What is the status of existing measurements of the speed of gravity?


How does Delta baryon decay conserve angular momentum?


Why should an action integral be stationary? On what basis did Hamilton state this principle?


If electric fields can't pass through a grounded shield, how can a magnetic force be generated on moving charges outside a wire?

How can magnetic fields pass through a grounded shield?


What is the distance between two objects in space as a function of time, considering only the force of gravity?

Don't heavier objects actually fall faster because they exert their own gravity?


Why does a Gauge group have to be a compact Lie group?

Why is the Yang-Mills gauge group assumed compact and semi-simple?


What is the oscillating quantity in matter waves?


Relativity: easy spaceship scenario. easy questions

Does this count as moving faster than light?


Why is friction not dissipative in rolling motion?


Why is the light reflected at the same angle from mirror?


What is wrong with this method for FTL communication?

The choice of measurement basis on one half of an entangled state affects the other half. Can this be used to communicate faster than light?


Do photon inside event horizon exceeds speed of light?

How does light behave within a black hole's event horizon?


Is there an online course in Mathematical Methods for Physics, Covering Matrices and Vector Analysis?


Why do objects move when you apply a force that's equal in magnitude to the friction?

Given Newton's third law, why are things capable of moving?


Role of rubber elasticity in the pressure inside a balloon

Relationship between balloon size and pressure


Does the (relativistic) mass change? Why?


What is the phase (state of matter) of a single particle?


Is the position of matter discrete in universe?


Can someone explain renormalization in high school language?


For how much energy does the heat generated in earth's interior account in earth's total energy budget?

How much heating does Earth inner core provide to the surface?


Why is normal contact force acting on a person in an elevator during a free fall 0?

Why does a free-falling body experience no force despite accelerating?


Will a larger or smaller body of water lose heat faster?


Maxwell in multiple dimensions: What happens to curl?


If gravity can be disrupted by larger forces, why does the moon orbit the Earth instead of the Sun?

Why does the Moon not revolve around the Sun directly?


Newtons third law explanation on a push of table


Resistor circuit that isn't parallel or series


Can two simultaneous independent measurements circumvent uncertainty?

Uncertainty principle and multiple observers


Magnetic field due to a coil of N turns and a solenoid

Why is the B field of a solenoid equal to $\mu_0 i n$ while that of a loop is $\frac{\mu_0 i R^2}{2(R^2+z^2)^{3/2}}$?


Why a body can not be accelerated to speed of light in vacuum?

Accelerating particles to speeds infinitesimally close to the speed of light?


What is a good introductory book on quantum mechanics?


What was the size of universe at big bang


Is the speed of gravitational waves lower in a medium?

Do gravitational waves slow down as they pass through matter?


How viable is using Quantum Entanglement for long distance communication?

Quantum entanglement as practical method of superluminal communication


Is the linearity of transformation of intervals postulate in SR?

Interval preserving transformations are linear in special relativity


Quantum spin, tensor product: a long time relationship

Should it be obvious that independent quantum states are composed by taking the tensor product?


Why is TV remote's infrared wave shown by a camera as purple light, why not red or something else?


Analysis of a jar falling with a fly inside

Acceleration of a Free-Falling System with Center-of-Mass Change


How is gold (the element) gold (the color)?


If a car collides with an immovable, unbreakable wall, does energy lost or force determine damage?

Please help understanding the difference between force and kinetic energy for an object hitting a wall?


Is Abraham-Lorentz Force problem still unresolved?

The problem of self-force on point charges


Dimensional analysis with height and time


Did time exist before the Big Bang and the creation of the universe?


Is the wave-particle duality a real duality?


Help me understand this example about FTL = time travel

Does superluminal travel imply travelling back in time?


Misconceptions about the Klein-Gordon and Dirac equations and their problems

Why can't the Klein-Gordon equation explain the hydrogen atom but the Dirac equation does?


How is the concept of "work done" useful?

What is behind the definitions of work and energy?


What is the spin rotation operator for spin > 1/2?


Why in the relativistic quantum mechanics $ \gamma_4$ name is not used instead of $ \gamma_5$?


Two body vacuum solutions of Einsteins field equations


Do we know why speed of the light in vacuum is exactly 299792458 $m/s$?

The origin of the value of speed of light in vacuum


The Time That 2 Masses Will Collide Due To Newtonian Gravity


What does index $\mu$ in $\partial_{\mu}$ mean?


Why do metals only glow red, yellow and white and not through the full range of the spectrum?

What causes a black-body radiation curve to be continuous?


If humans were able to catch all sun energy reaching the earth for their use, will the climate change?


if white things reflect light and mirror reflect light why don't they look the same

What is the difference between a white object and a mirror?


What happens when there are different classical trajectories before and after Wick rotation?

How to understand "analytical continuation" in the context of instantons?


Interesting topics to research in mathematical physics for undergraduates


why does unhinged body rotate about centre of mass when off-centre force is applied?

What is the proof that a force applied on a rigid body will cause it to rotate around its center of mass?


Can Newton's law of cooling explain Mpemba effect?

What is the status of Mpemba effect investigations?


Which law is more fundamental, Gauss's law or Coulomb's Law?


What is the relation between electromagnetic wave and photon?


Do gravitational waves violate conservation of baryon number?

Does a planet/star itself lose mass when it 'emits' gravitational waves?


If you hover just above the event horizon of a black hole, would you see the future of the universe?

Does someone falling into a black hole see the end of the universe?


Why is $i$ used in the equations for quantum mechanics?


How did planets have an elliptical orbit in the first place?


Where does the partial derivative come from in Sakurai's derivation of the momentum operator?


How many of which particles are in Hawking radiation?


Derivation of the Infinitesimal Translation Operator

Where does the $i$ come from in the Schrödinger equation?


Euler's equations of rigid body motion from least action principle


Apparent Violation of Newton's $3^{\text{rd}}$ Law and the Conservation of Momentum (and Angular Momentum) For a Pair of Charged Particles


What would you see standing on black hole just above the event horizon ? Will you look through past and future of the universe?

Practical time travel: time dilation above the event horizon


What if the universe is rotating as a whole?


Why do I see better under water using swimming goggles?


What do operations on single Qubits of Unfactorable Superpositions Do?

Help on applying a Hadamard gate and CNOT to two single q-bits


Why are periodic boundary conditions used for the derivation of phonons?

Interpretation Born-Von Karman boundary conditions


Stanford: "Objects in spacetime all move at constant speed $c$." Are they right?

Why are objects at rest in motion through spacetime at the speed of light?


Physics 3 recommended book with solutions


Layman's explanation and understanding of Einstein's field equations


A star starts at rest at infinity, how do you calculate the kinetic energy of the star when it crosses the event horizon of a black hole?

Will an object always fall at an infinite speed in a black hole?


Is this equation $\nabla_a\sqrt{-g}=0$ correct?

Why is the covariant derivative of the determinant of the metric zero?


In what other fields of physics does "math break down"?

Why does gravitational singularity break the laws of physics?


How is mass of observable universe calculated?

How do people calculate proportions of dark matter, dark energy and baryonic matter of the universe?


Does the (relativistic) mass change? Why?


Would forcing a photon to travel under $c$ even after it leaves a medium break Relativity?


What is the metric at the center of a star?

What is the general relativity explanation for why objects at the center of the Earth are weightless?


Would time freeze if you could travel at the speed of light?


Why do electrons/photons create an interference pattern in the double slit experiment?

Are double-slit patterns really due to wave-like interference?


Can the passage of time be measured in the absence of motion?


How to choose characteristic length in Reynolds number?

What is actually the characteristic length in fluid dynamics description?


Charged gravity: what magnitudes, if any, would be consistent with observations so far?


If we can't clone quantum states, then how does stimulated emission work?

Stimulated emission and No cloning theorem


Why doesn't electricity and magnetism distort space as well?

Why is spacetime curved by mass but not charge?


A list of inconveniences between quantum mechanics and (general) relativity?


Can one do the maths of physics without using $\sqrt{-1}$?


Does an electron occupy a definite volume?


Connection between Gauge Fixing Term and Gauge Condition

What is the constraint on the Gauge Potential in the Covariant Gauges?


Why doesn't the Moon fall onto the Earth?


What is the difference between weight and mass?


what is causing gravitational pull in between massive bodies?

What is the cause of gravitional force of attraction?


Why in series combination of circuit has same amount of current flow in every conductor?

Current in series resistors and voltage drop in parallel resistors


If a photon is exists in 'timeless' state, how can objects around it move?

Would time freeze if you could travel at the speed of light?


Relative time/space - Two clock thought experiment


What are the characteristics of the magnetic field surrounding a human brain?


Paradox with Gauss' law when space is uniformly charged everywhere


Was Aristotle Actually Correct About Gravitation?

Don't heavier objects actually fall faster because they exert their own gravity?


What allows us to distinguish between two different voices even if they're singing the same note?

What are those characteristics by which every sound can be identified uniquely?


If the universe is infinite, should there be a duplicate of me with probability 1?

Are the implications of an infinite universe necessarily so unsettling


What does the Pauli Exclusion Principle say about a superposition of spin states?


What underlying structure/framework defines the charge of an antiparticle or regular particle (specifically a proton)?

Identification of particles and anti-particles


How did Isaac Newton figure out how the law of gravity worked?

How was Newton able to guess that gravitational force is inversely proportional to distance squared?


How is it possible for an infinitely large charged plane to cause the same electric field regardless of distance?

Explanation for $E~$ not falling off at $1/r^2$ for infinite line and sheet charges?


How much iron would I have to shoot into the Sun to blow it up?


Why does U-235 split into barium and krypton in nuclear reactors?

Does Uranium-235 always split into Krypton and Barium in nuclear fission?


EM Fields Transmitted from an antenna and photons

How can we interpret polarization and frequency when we are dealing with one single photon?


Learning Roadmap to Mathematical Physics


Do Category Theory and/or Quantum Logic add value in physics?


What's the biggest cube you could have before gravity rounded it?


Use a Delayed Choice Quantum Eraser to communicate Faster Than Light

What's wrong with this experiment showing that either FTL communication is possible or complementarity doesn't hold?


why does a change in velocity cause length contraction, mass gain and the slow down of time?


Are we traveling through time at the speed of light?

Why are objects at rest in motion through spacetime at the speed of light?


Starter's book on Quantum Mechanics (more general and simple books than full QM textbooks)

What is a good introductory book on quantum mechanics?


Infinite universe, big bang = no singularity?


Why is my breath hot when i open my mouth all the way, but cold if I blow like a whistle?

Why does the air we blow/exhale out from our mouths change from hot to cold depending on the size of the opening we make with our mouth?


How does electricity produce magnetisim?

How do moving charges produce magnetic fields?


Will acceleration rate of expansion of space become faster than speed of light?


Working out velocity (including air resistance)

Equations for an object moving linearly but with air resistance taken into account?


Does Expanding Universe conflict with the Thermodynamics 3rd Law?

How can it be that the beginning universe had a high temperature and a low entropy at the same time?


Why are L4 and L5 Lagrange points stable as points and not part of a circle?


Can we really see new objects in future?

How far away must a galaxy be for its light never to reach us due to the expansion of the universe?


Can an aluminized blanket hide a person from thermal cameras?

Is there a portable method of preventing all IR radiation from being emitted?


Why is there no absolute maximum temperature?


What is the fastest speed that a massive object can travel at?

Accelerating particles to speeds infinitesimally close to the speed of light?


Interstellar Movie: Black hole shown in the movie

What does this depiction of a black hole in the movie Interstellar mean?


How did Schrödinger come up with his equation?

What inspired Schrödinger to derive his equation?


Why the speed of light in vacuum is same in all inertial reference frames?

Why and how is the speed of light in vacuum constant, i.e., independent of reference frame?


Why is space (almost) flat? Is it because masses are approximately homogeneously distributed?

Why does inflation (the inflaton field) push Omega down closer to zero (flatten the universe)?


How can a singularity have infinite density?

Why does a black hole have a finite mass?


Why can't we define a unique wavelength for a short wave train?


Sign convention for the Minkowski metric $\eta_{\mu\nu}$

Advantages of using different metric signatures in relativity and QFT


Does the uncertainty principle affect event horizons?

The uncertainty principle and black holes


Why charge distribution is greatest at pointy edges of a surface?

Why is electric field strong at sharp edges?


What type of relationship should the speed of sound vs. air temperature graph have? Linear? Quadratic? Exponential?

How can the speed of sound increase with an increase in temperature?


Why charge density is higher in the sharp edges of conductor?


How Is the Inertial Mass Different From the Gravitational Mass?

What's the difference between the five masses: inertial mass, gravitational mass, rest mass, invariant mass and relativistic mass?


Books for Condensed Matter after Ashcroft/Mermin


Arranging solenoids into a sphere to create a magnetic monopole?

What is the magnetic field inside hollow ball of magnets?


A water pipe from sea level to beyond the atmosphere


Why color of dress changes when water falls?


Why do physicist accept the idea of singularities?

Do singularities have a "real" as opposed to mathematical or idealized existence?


How should a physics student study mathematics?


Total angular momentum of a planet orbiting a star


Do eyeballs exhibit chromatic aberration?


Why is there no massless spin 1/2 particles with charge? Is there any underlying theory?


Complex variables in classical mechanics

Can one do the maths of physics without using $\sqrt{-1}$?


Why does the light travel slower in denser medium?

What really causes light/photons to appear slower in media?


Do integrals of position make any sense? Do they have an application?


How large can an atom get? What's the farthest an electron can be from its nucleus?


If it was possible to dig a hole that went from one side of the Earth to the other...


interaction of mathematical structures (rephrased)

interaction between mathematical structures


Angular Velocity after a frictional impulse

Is there a 2D generalization of the coefficient of restitution?


Rutherfords alpha scattering conclutions?

Alpha scattering, observations and conclusions


Is reflection of light due to absorbtion and reemission?


Vortex in liquid collects particles in center


Is rigorous functional analysis useful for theoretical physics?


Displacement current in charging capacitor

In terms of the Ampere-Maxwell law, why is $\vec {E}=0$ in a wire of a capacitor circuit?


Newton's third law. how things can move?

Given Newton's third law, why are things capable of moving?


Two coffee beans in a cup of water + vibrations = gravity?

Why does a cork float to the side of a glass?


Why do objects float in liquids denser than themselves?


If photon energies are continuous and atomic energy levels are discrete, how can atoms absorb photons?


Is a scaled-up aircraft carrier 'ski-ramp' a viable system to impart enough velocity to significantly assist a spacecraft to orbit?

What is the possibility of a railgun assisted orbital launch?


Continuous and discrete basis of Hilbert Space

Hilbert space of harmonic oscillator: Countable vs uncountable?


Is it possible for information to be transmitted faster than light by using a rigid pole?


How does quantum dynamics explain interference of two light beams

Does a photon interfere only with itself?


Tension in a string in equilibrium (Y&F University Physics section 4.5)

Why I think tension should be twice the force in a tug of war


How is the space vacuum not strong enough to pull the atmosphere off?


What is actually the characteristic length in fluid dynamics description?


Can the speed of light actually changes?


Is Planck length the smallest allowable difference between wavelengths?

Does the Planck scale imply that spacetime is discrete?


How can a railcar withstand high pressure but fail under a vacuum?


Good mathematical introduction to loop quantum gravity


Are velocity and acceleration smooth quantities?


Vector addition in speeds close to that of light

If I am travelling on a car at around 60 km/h, and I shine a light, does that mean that the light is travelling faster than the speed of light?


Do we have any evidence of slower-than-light neutrinos?


Angular velocity: $\omega = vr$ or $\omega = v/r$?


Is it diffraction I see when I closely look at my finger(s)?

Why can I see my fingers connected when they haven't touched?


Trouble with operator-sum representation of a quantum operation


Is it possible for a punch traveling at relativistic speeds to miss the target because of length contraction (from both reference frames)?

Hole-and-nail paradox in special relativity


Will a change in reference frame produce light?

EM wave generation from different frames of reference


The role of the variable $r$ in gravitational time dilation?

Exact meaning of radial coordinate of the Schwarzschild metric


Possible explanation of dark matter/dark energy?

Could dark energy be the effect of gravity at great distances?


How can a particle in a medium ever travel faster than light?


Physical interpretation of Glauber states

What exactly is a coherent state and why is it interesting?


How to compute partial trace of $U ( \rho_A \otimes \rho_B) U^+$?


Will there be translation + rotational motion?

Force acting on a simple rigid body in space


How to use the generating functional for connected functions to compute connected diagrams?


How will the (anti)commutation relation between two different fermion fields look like?

Fermions, different species and (anti-)commutation rules


Why there is no diffraction in the microwave oven's door?


Validity of naively computing the de Broglie wavelength of a macroscopic object


why is pressure more convenient than force while dealing with fluids?

Define Pressure at A point. Why is it a Scalar?


Superposition of discrete level and continuum: Electron bound and free

Is it possible that we have a physical state which is a mixture of discrete eigenstates and continuous ones?


What is the meaning of the integral of position?

Do integrals of position make any sense? Do they have an application?


How does time look relatively in a gravity well?

Gravitational time dilation, does time of the observer at a lower gravitational potential looked slowed down in the frame of the higher one


About the real reason why paper doesn't fall in HALF-FILLED inverted cup

About an upside down cup of water against atmosphere pressure


Why friction between two smooth surfaces is high?

What happens when two smooth surfaces touch?


Self Study Textbook Progression from QM to QFT?

A No-Nonsense Introduction to Quantum Field Theory


Self Study Textbook Progression from Griffiths QM to QFT?


Variations of earth's magnetic field strength among different geographical locations


Why doesn't water turn into liquid after boiling it?

How does water evaporate if it doesn't boil?


If we had a radio antenna produce visible light?

Radio antenna producing waves in the visible spectrum


In a circuit one light-second long, does it matter where in the circuit the switch is placed?


How can the speed and the mechanics of light be similar to the speed and the mechanics of gravity?


Total energy of a simple pendulum proportional to the square of the amplitude?

Why is energy in a wave proportional to amplitude squared?


How to understand photons in terms of EM force carrier?


Traveling to the future is possible, but not to the past?

Is time travel possible? Is it possible to go back in time?


How can we say that difference in energy between 99.99% and 100% of speed of light is infinite?

Why is travelling around the speed of light a problem?


How fast does water have to be moving for it to gain a lot of heat?

After what speed air friction starts to heat up an object?


On the surface, is the law of maximum entropy production analogous to the principle of least action?

Entropy and the principle of least action


How is pressure an intensive coordinate?


differences between the real image and virtual image


Why is the electric component of a light field more important than the magnetic component?

Why does the electric field dominate in light?


Black Holes should take infinite time to form with the increase in mass to form one

How can anything ever fall into a black hole as seen from an outside observer?


Why are so many forces explainable using inverse squares when space is three dimensional?


If temperature is amount of kinetic energy of particles, then how can there be a cold breeze?


Do we have theories about why gravity exists/how it works?


Does a rocket engine apply more power as the rocket's speed increases?

Where does the extra kinetic energy of the rocket come from?


Is the speed of light the only speed that exists?

Why are objects at rest in motion through spacetime at the speed of light?


What would a relativistic set of 'suvat' equations look like?

What is the displacement of an accelerated and relativistic object?


Confusion about validity of work energy theorem

Validity of work-energy theorem in presence of non-conservative forces?


Will the Earth ever show synchronous rotation? Why and when?


What is the equation that determines evaporation rate for water?


Need help understanding electric potential in circuits!

How do the different types of energy apply to voltage in a circuit


Staggered Indices ($\Lambda^\mu{}_\nu$ vs. $\Lambda_\mu{}^\nu$) on Lorentz Transformations


Explaining halls effect and magnetic induction


Is there a definition of "direction" in physics?


Eq. (2.4.7) of Weinberg, "Lectures on QM" from eq. (2.4.6)

Does the canonical commutation relation fix the form of the momentum operator?


How does non-Abelian gauge symmetry imply the quantization of the corresponding charges?


How to check if the relativistic Lagrangian of a free particle is Lorentz invariant?

Lagrangian for free particle in special relativity


Why does the air flow faster over the top of an airfoil?


What will be the equation of a wave on a string?

What is the difference in the uses of $\omega t$ and $kx$ in wave equation?


What is the qualitative cause for a driven oscillator to have a max. amplitude during resonance?


Why are stars, planets and larger moons (approximately) spherical in shape (like, the Sun, the Moon, the Earth, and other planets)?


What is the real meaning of Planck's constant?

What is the real interpretation of Planck's constant and what are its origins?


Net work done on the body when we lift it and put it on the table is zero?


Constancy of the Speed of Light in a medium

What is the mechanism behind the slowdown of light/photons in a transparent medium?


If I'm floating in space and I turn on a flashlight, will I accelerate?


Why can't an energy level exist containing 0.9 electron wave wavelengths? Why must it be a whole number?

Electron shells in atoms: What causes them to exist as they do?


Why, exactly, can't two field lines cross?

Why can two (or more) electric field lines never cross?


Is the E-Cat by Andrea Rossi et al. proof that cold fusion can work?

Is the E-cat by Andrea Rossi et al. for real?


What has been proved about the big bang, and what has not?


What topics should I develop complete concepts in before I begin the derivation of GR?


Do celestial objects experience drag from the near vacuum of space/does the near vacuum have a mean velocity?


Why do we use Root Mean Square (RMS) values when talking about AC voltage


How was it proven that a quantum entanglement measurement of particle A, affects properties of particle B

How do we know that entanglement allows measurement to instantly change the other particle's state?


Why is the phase of reflected wave during formation of standing waves 180 degrees?

What happens to the energy when waves perfectly cancel each other?


Which position and momentum distributions arise from some wave function?

Reconstruction of "wavefunction" phases from $|\psi(x)|$ and $|\tilde \psi(p)|$


How can dissipative/friction terms be incorporated into a Lagrangian?

Lagrangian and Hamiltonian EOM with dissipative force


How to prove $\hat{p}|x\rangle=i\hbar\frac{\partial}{\partial x}|x\rangle$,using $[\hat{x},\hat{p}]=i\hbar$?

What does the Canonical Commutation Relation (CCR) tell me about the overlap between Position and Momentum bases?


Why is it legitimate to only observe motion, but call it time, such that concepts like “the relativity of simultaneity” are seen as possibly genuine?

Where in, Einstein’s "On the Electrodynamics of Moving Bodies" (Relativity), is “Time” reasonably shown to exist, or why is it a valid assumption?


What property of medium is directly related to light propagation speed in that medium?

Looking for the actual reason of refraction explained precisely without analogies


Can the half-life of a free neutron be calculated or is it just empirical?

Why is the (free) neutron lifetime so long?


Can momentum be conserved in a perfectly elastic collision?


Are Lockheed Martin nuclear fusion claims realistic?


How can black holes have electric charge and spin?

How can a singularity in a black hole rotate if it's just a point?


Why is there no absolute maximum temperature?


Given Newton's third law, why are things capable of moving?


What would be the best way to explain color confinement in quarks?


Speed of sound and Break the sound barrier

Why do vapour cones form around jet fighters?


Has NASA confirmed that Roger Shawyer's EmDrive thruster works?


Understanding better this physical phrase

How do we know what type of gauge field to add to a theory?


Is ohm's law violated in electric transmission lines?

Why the current decreases with increase in voltage in transmission lines? But according to Ohm's law current should increase with Voltage


Why do we fall down when the bicycle slows down?

Why doesn't a bike/bicycle fall if going with a high speed?


Do all phases of ice look the same visually?


Collision between stationary and moving vehicle


How to (safely) measure the surface area of a human body?


Which charge actually moves to constitute current? Positive or negative?


what does it truly mean for there to be a max speed?


Why are austenitic stainless steels not ferromagnetic?

Why Inox Steel doesn't interact with magnets?


What is the difference between a tensor, vector, and a matrix?


Colors observed as an heating effect on steel

What makes metal change its color during heating?


What is the cleverest way to calculate $[\hat{a}^{M},\hat{a}^{\dagger N}]$ when $[\hat{a},\hat{a}^{\dagger}]=1$?


Why do we say that irreducible representation of Poincare group represents the one-particle state?


How fast is information transferred between the two entangled particles?


A planet with a straight tunnel through it

Period of oscillation through a hole in the earth


Integrating a dot product gives wrong sign for work done


If I travel almost side by side with light, how fast does light go near me?


What is time, does it flow, and if so what defines its direction?


Why aren't Faraday's law of induction and Maxwell-Ampere's law symmetric?

Why aren't Faraday's law of induction and Maxwell-Ampere's law (without sources) symmetric?


Can stimulated emission happen in nuclear energy states?


What happens when I grab a hanging rope mid-jump?

Force Transfer Between two bodies linked by a rope


Equivalence Principle - mass on table example

Why does holding something up cost energy while no work is being done?


Why are radians more natural than any other angle unit?


What happens after the light from the sun has travelled its entirety?

Do individual rays of light lose energy via the inverse square law?


Why do different materials absorb and reflect different wavelengths of light?

What is the actual mechanism behind the reflection of various colored light by material of different color?


How is the mass of an electron determined?

How to measure the mass of the electron?


Is there a maximum amount of photons that can exist in a certain amount of space?


Prerequisites for Classical Mechanics by V.I. Arnold

Prerequisites for classical mechanics by Susskind


Would running against the spin in a rotating space station reduce the pseudo gravity?

Is it possible to counter-act centrifugal force by moving at the same speed in the anti-spin direction?


Why is no heat produced when dielectric inserted slowly in charged capacitor

Heat produced when dielectric inserted in a capacitor


What does a sound of infinite Hz sound like?


Speed of sound faster in less dense air?

What causes an increase in sound speed in a medium?


Is a "Perfect" Vacuum theoretically possible

Why is it impossible to have a perfect vacuum?


Why do we ignore rotational energy in monatomic gases?

In counting degrees of freedom of a linear molecule, why is rotation about the axis not counted?


Doesn't the Big Bang negate the law of conservation of matter?

Conservation law of energy and Big Bang?


Negative sign in rotation operator (quantum mechanics, angular momentum)

Negative sign in rotation operator again


Why when I put a teabag into microwaved water does the water fizz?

Why does boiling water in the microwave make a cup of tea go weird?


Are atomic energies increasing as the Universe expands?

Why does space expansion not expand matter?


How is the classical twin paradox resolved?


How did Newton figure out the law of gravity?

How was Newton able to guess that gravitational force is inversely proportional to distance squared?


How can a photon have energy when its mass is zero?


Comparing the orbit radius of two spherical objects

Kepler problem in time: how do two gravitationally attracted particles move?


Why do certain types of sound seem to fade faster?


Radiation– white vs black house, hot or cool?


What is the electrostatic force between charges if they separated by a combination of dielectric media?

What is the force between two charged objects when the space between them is partially filled by a dielectric medium?


Does a particle annihilate only with its antiparticle? If yes, why?


Is the Earth the center of the Solar System?

Why do we say that the Earth moves around the Sun?


What's the difference between cosmic time and conformal time?


Phase shift of 180 degrees of transversal wave on reflection from denser medium


Fluid Dynamics applied to Aircraft wings


Is it possible to give photons an electric charge?

If electromagnetic fields give charge to particles, do photons carry charge?


Why does deflating baloon spurting through the air make circular motion?

Why does a balloon spiral in the air instead of moving in a straight line?


How is the position of an electron made?

If I want to measure an electron how would I do it?


Does cosmological time expand like space does?


Expansion of universe faster then speed of light?


Reflection of light at a microscopic level


what are the relativistic/cosmological implications on a long rigid body?

Extended Rigid Bodies in Special Relativity


How does quantum trapping with diamagnets work?


How can heaters using the same type of fuel be more or less efficient than each other?


Quasiclassical QM for centrally symmetric fields


Space is expanding so what is time doing?

Does time expand with space? (or contract)


Arguing on dimensions of logarithms and exponentials

Exponential or logarithm of a dimensionful quantity?


How does curved space make an obejct move toward Earth?

How does "curved space" explain gravitational attraction?


Why do some elements burn different colors?


About Planck tension in strings theory as stated in "The Elegant Universe"


What are the pieces of evidence that universe is expanding?

Is redshift the only way by which we can tell that space is expanding?


The LIGO Gravitational Wave Detection: How frequent in the observable universe?

What was the rate of Black Hole - Black Hole mergers expected to be detected by LIGO prior to GW150914?


Is the Poynting vector non-zero when two magnets are placed on either side of a charged capacitor?

Does a nonzero Poynting vector mean that there is propagation of energy?


In what cases do we use the Routh Function?

Working with a Routhian for a specific system


Electric field inside the "Dees" of a Cyclotron and why no "Cups"


Creating a Magnetic Monopole through a torus

What happens to the magnetic field in this case?


Direction of the lightbeam in SRT thought experiments


What is Moment of Inertia of a cube about an axis passing through its centre and perpendicular to one of its faces?

How to calculate the moment of inertia of a solid cube?


Current is a scalar quantity, but how does it have a definite direction?


Why the earphones in the pocket always form knots? How to explain this problem in Maths?

Why do earphone wires always get tangled up in pocket?


Can we distinguish between two mass distributions in spacetime having the same effect over a test partlicle

Is every solution of Einstein field equations unique?


The LIGO Gravitational Wave Detection: have deep-mantle earthquakes been ruled out?

Is there absolute proof for gravitational waves?


What is the electric field in a parallel plate capacitor?


Noncoalescingِ drops on vibrating liquid surface


Derivation of Maxwell's equations from field tensor lagrangian


Anomalous expansion of water when heated


Heisenberg's uncertainty principle derivation in a ring

How can I solve this quantum mechanical "paradox"?


Difference between fermi energy level in metals and semiconductors

What's the difference between Fermi Energy and Fermi Level?


Can a naked eye see a single atom when it is resonantly driven by some laser beam?

Is fluorescence from a single atom/ion visible with the naked eye (e.g. in a strongly coupled trap or cavity)


Why is the speed of gravity the same as that of photons?

Do all massless particles (e.g. photon, graviton, gluon) necessarily have the same speed $c$?


Is the fabric of space time a real thing?

If the universe is 3D, how is space-time like a "fabric"?


What is a good mathematical introduction to QFT

Quantum Field Theory from a mathematical point of view


Apparent Violation of Newton's $3^{\text{rd}}$ Law and the Conservation of Momentum (and Angular Momentum) For a Pair of Charged Particles


Does a planet/star itself lose mass when it 'emits' gravitational waves?


How come the Earth is not crumbling into the core due to fact that the core is in the middle of it?

If the earth has gravity, why don't we all collapse to the center?


Why doesn't the momentum of the system change after an inelastic collision?

How can momentum but not energy be conserved in an inelastic collision?


Parallel universes: are there an infinite amount of universes?


Relation between centre of mass and axis of rotation

Do objects rotate around the torque vector or its center?


Why don't all gasses have infinite entropy?

Why isn't the entropy of gas infinite if there are infinite microstates available?


If all of Humanity ran East, would the Earth's rotation slow down?

Can humans control rotation of the Earth?


A question about magnets, energy, and forces

From where do the permanent magnets get energy from?


Is there a connection between Newton's law of universal gravitation and the area of a sphere?

Intuitive explanation of the inverse square power $\frac{1}{r^2}$ in Newton's law of gravity


Can a free electron accelerating in a gravitational field absorb photons?

Does a charged particle accelerating in a gravitational field radiate?


How a faster air flow creates a lower air pressure on an airplane wing?


What is the minimum time required to travel 1 light-year from Earth and turn back?

How long would it take me to travel to a distant star?


How can we explain Saturn's non-spherical shape in terms of forces?


Can we see enough of the universe to have a valid opinion on whether it's expanding?

What are the pieces of evidence that universe is expanding?


Is the force in Coulomb's law a vector field?

Is the electric force a vector or a vector field?


Why does a liquid exert pressure in all directions? More specifically why does a liquid exerts an upward force?

Why is pressure in a liquid the same in all directions?


Do gravitational lenses work on gravitational waves?


What is an intuitive explanation of units like $N \cdot m$?


Is there a quasi-particle corresponding to sound wave in air medium?


A momentum equation validity for all particles?

How to get the accurate relativistic momentum form for photons?


How do moving colliding particles create heat?


Ising model on lattices with (vertical side length) $\neq$ (horizontal side length)


Why is the d'Alembert's Principle formulated in terms of virtual displacements rather than real displacements in time?

D'Alembert's Principle: Necessity of virtual displacements


Why object in terminal velocity doesnt stop

How does a small object move with constant velocity when drag force is equal to its weight?


Is the frequency/wavelength of light modified when multiple light sources are combined?

How does light combine to make new colours?


Imagine a steel bar floating in space. Assuming the bar wouldn't break or bend, if I shoot a bullet at one end, would it rotate, fly away, or both?

If I push or hit an object in space will it rotate or move along a straight line?


How can a body have two axis of rotation at the same time?


When one monkey accelerates up a rope, what happens to the other?


Relativity's effects on centripetal motion


How does a simple weighing balance actually work?

Why does the weighing balance restore when tilted and released


Field at the center of a cube with positively and negatively charged faces

Electric field due to a uniformly charged FINITE rectangular plate


What kind of matter are black holes made of?


How to debunk this perpetual motion machine?


How to correct flares and sharply focus on my telescope when viewing planets.


How does gravity cause nuclear fusion in stars?


Centrifugal force when there is no friction

Direction of friction on particle placed on a rotating turntable


SPEED of LIGHT as photons reach black holes

The speed of light as it approaches a massive body


Is Dark Energy Pushing Us Or Pulling Us?

Could the acceleration of universe expansion be caused by gravity itself?


Spinning theoretical object moving faster than the speed of light

Is it possible for information to be transmitted faster than light by using a rigid pole?


Why earth looks always flat when it is round

What is the simplest way to prove the Earth is round?


What is Work? What does the quantity suggest intuitively?


What is the correct way to handle significant figures when calculating compound uncertainties?

When do I apply Significant figures in physics calculations?


How can water evaporate at room temperature?

How does water evaporate if it doesn't boil?


Explanation: $H^{-1}$ is the time-scale over which the universe changes by $\mathcal{O}(1)$

Hubble time, the age of the Universe and expansion rate


Does the pilot of a rocket ship experience an asymptotic approach to the speed of light?


What is the symmetry associated with electric charge conservation

What is the symmetry which is responsible for preservation/conservation of electrical charges?


Do circular wheels maximize mechanical efficiency?


Should I learn Classical Physics if I want to learn Quantum Physics?

What is the math knowledge necessary for starting Quantum Mechanics?


Multiple Classical Limits of a Quantum Theory

How do I know how many classical limits (if any) a given quantum theory is going to have?


How does negative energy from Hawking Radiation cause a Black Hole to shrink?

Black holes and positive/negative-energy particles


how much helium would you need to pick up one kilogram on mars

How much lift does the average latex helium filled party balloon produce?


Are gravitational time dilation and the time dilation in special relativity independent?


How to describe arbitrary accelerations in special relativity


Which is a good and short book for foundations of quantum mechanics?

What is a good introductory book on quantum mechanics?


Is time travel possible? Is it possible to go back in time?


Change in F vs x graph if spring is torn in half?

Is the spring constant $k$ changed when you divide a spring into parts?


What role does wavelength play in the identity of a photon?

What determines color -- wavelength or frequency?


Why don't we consider the electromagnetic field in the equations of Bohr's theory of atoms?

Why don't electrons crash into the nuclei they "orbit"?


How is a second measured? And why is it measured that way?


Mathematical form of the de facto repulsive "force" associated with the Pauli Exclusion Principle

Is the electromagnetic force responsible for contact forces?


How does a bowl of hot water move by itself?


Why is electric flux zero if my point charge is outside of a sphere?


What are the reasons for accepting Coulomb's law?


What is the deep reason of length contractions and time dilations?

Is gravitational time dilation different from other forms of time dilation?


Showing two wavefunctions are proportional to one another


how photon gets accelerated instantaneously to speed of light?

Does a photon instantaneously gain $c$ speed when emitted from an electron?


Why does the Moon have circular motion while a falling apple has one-dimensional motion?

Why doesn't the Moon fall onto the Earth?


If time is like space, why entropy always increases with time?


Relation between radius of curvature and heat produced at focus when concave mirror is kept in sunlight

What temperature is achieved in focus point by 5000 flat 1x1cm mirrors onto a satellite dish?


Does a humming bird eating flower juice in an accelerating train, need to fly forward or just fly to remain at the same place?

Will a helicoper which is hovering inside a closed box move with the box when we move it?


How can we solve 2D rigid body collision?


How does bending in space-time caused by mass energy translate into acceleration of object?

How does "curved space" explain gravitational attraction?


Why do all the planets of the solar system orbit in roughly the same 2D plane?


If a mass moves close to the speed of light, does it turn into a black hole?


Can a uniform circular motion be considered as simple harmonic motion?


In practical, how to find the friction of rubber vs plastic?


Why does mass not matter on how quickly an object falls?

Don't heavier objects actually fall faster because they exert their own gravity?


Why does the aorta spray blood when atmospheric pressure is higher than blood pressure?


Why is it impossible to remove the crease from folded paper?

Creasing of a material at the molecular level


Entering a black hole, jumping into another universe---with questions


How increases the flow rate of a fluid by increasing pipe diameter?

How does the radius of a pipe affect the rate of flow of fluid?


Electromagnetic radiation of charges under accelerations

How and why do accelerating charges radiate electromagnetic radiation?


Is quantization of energy a purely mathematical result or is there a fundamental reason behind it?

Reason for the discreteness arising in quantum mechanics?


How exactly does potential difference remain the same across the branches in a parallel connection of capacitors?

Why are potential differences equal across two capacitors in parallel, but charge on each capacitor is not?


Do two beams of light attract each other in general theory of relativity?


Why small planets are not attracted by larger planets due to gravitational force?

Why doesn't the Moon fall onto the Earth?


What is the difference between a neutrino and an antineutrino?


What quantum mechanical effect allows light to gain it's speed when it moves from another medium back into air/vacuum?

How does light speed up after coming out of a glass slab?


Is there/could there be a theoretical absolute hot?

Is there an upper limit to temperature in thermodynamics or statistical mechanics


Hottest tea during your breakfast problem

Does tea stay hotter with the milk in it?


Why during annihilation of an electron and positron 2 gamma rays are produced instead of 1?

Why can't a single photon produce an electron-positron pair?


Why is the center of buoyancy located at the center of mass of the displaced fluid volume?


What causes the chaotic trajectory of a balloon going flat?

Why does a balloon spiral in the air instead of moving in a straight line?


What does it mean for a particle to have volume?

What is the mass density distribution of an electron?


How small must an object be in order for it to be subject to the laws of quantum mechanics?

Can actual quantum effects occur on a macro scale?


How to decide whether light shows particle of wave nature?

Which side of wave-particle duality to choose in a given situation


What happens to the magnetic field in this case?


Dark matter and relativistic mass change


Discrete energy and black body radiation

How does quantization solve the ultraviolet catastrophe?


What's stopping two independent observers from measuring the speed and position at the same time, separately?

Uncertainty principle and multiple observers


Why do two beams of light pass through one another without interacting?


Why is the speed of light defined as 299792458 m/s?


Sound difference between musical instruments

What are those characteristics by which every sound can be identified uniquely?


Does an expanding universe assume a space within which the expansion is happening?

If the universe is expanding, what is it expanding into?


Are Lorentz transformations linear transformations?

Interval preserving transformations are linear in special relativity


Relation of gravitational pull with no air friction

Why do two bodies of different masses fall at the same rate (in the absence of air resistance)?


Gravitational acceleration at half Earth's radius


What exactly does the *frequency* of a photon mean?


Gravity and the Second Law of Thermodynamics

How does the formation of a solar system not break the second law of thermodynamics?


How can time-travel be possible if speed is relative?

How is the classical twin paradox resolved?


How to prove when electron spin is perpendicular to linear momentum, orbital angular momentum can't be 0

The relationship between angular and linear momentum


How does the Higgs Boson gain mass itself?


Why is momentum conserved in an inelastic collision and kinetic energy is not conserved?

How can momentum but not energy be conserved in an inelastic collision?


What moves an object? Momentum or Kinetic Energy?

Newton's third law does not apply to the kinetic energy formula?


Gravity doesn't seem to work the way it is supposed to

Intuitive understanding of centripetal vs. centrifugal force


If atoms are mostly vacuum, why are things so rigid around us?

Why doesn't matter pass through other matter if atoms are 99.999% empty space?


Why is there a static frictional force on an object that rolls down a ramp?

Consider a horizontal surface with or without friction. Ideally, will a wheel rolling without slipping roll forever in both cases?


When they say that the universe cooled after the big bang, where did the heat go?


Reference books for classical mechanics with good number of solved examples


Vector potential in presence of monopole

Can one introduce magnetic monopoles without Dirac strings?


What formula connects the moment of inertia and angular velocity?

Instantaneous angular momentum of a disc


Expanding universe and the speed of light

Why does space expansion not expand matter?


How can comets have sand dunes without atmospheric erosion?

What mechanism is responsible for the creation of these dunes on Comet 67P/Churyumov-Gerasimenko?


Unsure how resistors are connected? (Series/Parallel)

Resistors in para and series circuit, finding volt


Why did the big bang need to produce equal amounts of matter and antimatter?

Baryogenesis only at the Planck scale, or none at all?


extracting energy from cosmological expansion


Would days be longer as the polar ice caps melt?

Effect on length of day as the polar ice caps melt


Would equations for a spinning top be an (x,y,z) vector


How is expansion of universe seen locally?

Can the Big Rip really rip apart an atomic nucleus?


Expansion Mechanism in Loop Quantum Gravity

How is the expansion of space itself explained in LQG?


Can superstring theories predict our 4 dimensions?

Is 3+1 spacetime as privileged as is claimed?


What is a simple, effective, and physically consistent explanation of Bernoulli's principle (in the context of airfoil lift)?


Projectile motion with non-uniform gravitational acceleration

Projectile/orbital motion over very long distance


Earth-Based Nuclear Fusion - Choice of Reaction

Why is Helium-3 better than Deuterium for fusion energy production?


Is time travel possible? Is it possible to go back in time?


If electrons were positive and protons were negative, would life be different?

Why is the charge naming convention wrong?


Special relativity time dilation messing with my head

How is the classical twin paradox resolved?


How can buoyancy lift an object if the object is resting on the bottom?

Does an object need fluid under it to float?


Warm air goes up: reason on a microscopic scale?

What is the microscopic picture for warm air rising?


How do waves get reflected at open end of an organ pipe?

How can standing waves be produced in an open organ pipe if the ends are open?


What determines the forward voltage drop for a diode?


Could there be equivalence between anisotropic space and the presence of a field?

What is the explanation of the non-existence of magnetic monopoles?


Can relative speeds be greater than the speed of light?


How did temperature exist at the moment of Big Bang?

If temperature is dependent on mass, how did the early universe have a temperature?


Algebraic geometry and topology for string theory

Crash course on algebraic geometry with view to applications in physics


Why is the Ricci scalar the only independent scalar constructed from products of the metric and its first and second derivatives?

On the uniqueness of the Riemann-Christoffel tensor


How to make FBD in a vertical circle and a banked road?

Why is $R\cos{a} = mg$ in circular motion compared and not $R = mg\cos{a}$?


How does a single-photon double-slit experiment work?

Double Slit experiment with just one photon or electron


How is the classical twin paradox resolved?


Why doesn't dark matter interact with a black hole or get pulled in by it's gravity?

Can black holes grow via accretion of dark matter particles?


Can planets orbiting a binary star trace out an orbit in the form of an 8 (or $\infty$-sign)?

Might a planet perform figure-8 orbits around two stars?


Is there any detailed QFT-like description, at least tentatively, of Hawking radiation intensity?


What is a good book for self learning in geometry and topology and physics?

Book covering differential geometry and topology for physics


Why does the density of electric field lines make sense, if there is a field line through every point?


How does one start drawing electric fields?


Is there a mathematical proof show that $F=G\frac{m_1m_2}{r²}$?

Why $1/r^2$ and not another power of $r$ in Newton's law of gravitation?


Is there any such thing as a change in acceleration (ex: 3 m/s/s/s)?

Is it possible to have a rate of change of acceleration?


Do anyone know a good software that where I can easily find the metric from the stress-energy tensor?

Open source computer algebra systems for general relativity


Can we disconnect an object from the pull of gravity using some material?

Is it theoretically possible to shield gravitational fields or waves?


Why pouring milk from a height makes a chain shape?


Difference between speed of light and of bullet after passing through a barrier

How does light speed up after coming out of a glass slab?


Photon Emission/Absorbsion from the Photons Perspective

Does a photon in vacuum have a rest frame?


What is the cause of rolling friction? & why is it less than sliding friction?


Ways for undergrad to understand physics research?


Creating an arbitrary state of the quantum simple harmonic oscillator


Local translations included in covariant general coordinate transformation


Is the collapse of the wave function inherently time asymmetric?


Quantum physics and constructable numbers

Does the Planck scale imply that spacetime is discrete?


How can I use Einstein's field equations to find the metric tensor?

Finding the metric tensor from the Einstein field equation?


How does the equation $1/I = r/E +R/E$ relate to $ y=mx+c$?

Current against the inverse of resistance graph, $I = V/R +c$


How two electric charges know about each other?

How is the electostatic field propagated by the vacuum? How does a charge feel the presence of another charge when there is NOTHING between them?


Why isn't all of physics based on other rates of change

Why are there only derivatives to the first order in the Lagrangian?


Why should I believe that matter does not expand along with the space between it

Why does space expansion not expand matter?


Can a "flat function" be a particle trajectory?

Infinite series of derivatives of position when starting from rest


Have we really measured the wavelength of light?

How do you measure wavelength/frequency of light


What's the significance of neutrino oscillations?

Why do neutrino oscillations imply nonzero neutrino masses?


Can we travel faster than the speed of light?

Is it possible for information to be transmitted faster than light by using a rigid pole?


What happens to light in a perfect reflective sphere?


Is 3+1 spacetime as privileged as is claimed?


What--is the Ultimate Limit of heat based off c?

Why is there no absolute maximum temperature?


Could the randomness of quantum mechanics be the result of unseen factors?

Is the universe fundamentally deterministic?


Can light projection on a wall travel faster than the speed of light?

Is it really possible to break the speed of light by flicking your wrist with a laser pointer?


Given Newton's third law, why are things capable of moving?


Why can I see through a window but not a wall?


Vertical filaments during Atomic bomb explosion

What are the white lines in some nuclear bomb test photos?


Why can't electric field lines intersect each other?

Why can two (or more) electric field lines never cross?


Why do prisms work (why is refraction frequency dependent)?


How long will the Universe's hydrogen reserves last for?


What is a good Primer on the subject of Physics?


A vector in a rotating frame. Find the rate of change of this vector ('particular step derivation')

How to derive relation for time derivative in a rotating reference frame


Negative Mass's Effect on Gravitational Time Dilation

Would time speed up near a large body of negative mass relative to observers in micro gravity?


Basic physics question from a starting physics student

What is the cause for the validity of Newton's third law?


Effect of the tail of the cat in the falling cat problem


Can a satellite be put into orbit such that it will always remain directly over a city?

Can a satellite remain directly over a city?


How exactly does curved space-time describe the force of gravity?


Limits of Poisson's ratio in isotropic solid


How much energy can be extracted by lowering something into a black hole?

How much energy does lowering an object into a black hole generate?


Rapid acceleration does what to inertial frame clocks?

Rapid (ac/de)celeration in relativity does what to inertial clocks?


How far gravitational waves like the ones recently detecty are dangerous for life?

How close would you have to be to the merger of two black holes, for the effects of gravitational waves to be detected without instruments?


Can nonrelativistic QM, as used in bound states, be derived from QFT?

Is there a theorem that says that QFT reduces to QM in a suitable limit? A theorem similar to Ehrenfest's theorem?


Griffiths' argument that Newton's third law is invalid in special relativity

Is Einstein's Special Relativity completely inclusive of Newton's 3 laws of motion?


Why is the matter orbiting a black hole in the shape of a disk?

Why do all the planets of the solar system orbit in roughly the same 2D plane?


Why taking components of a component of a vector is invalid?


Can light be warped by a magnetic field?

Can a light be bent by a magnetic field?


Why don't big bang photons conserve mass and energy?

Redshifting of Light and the expansion of the universe


How is the classical twin paradox resolved?


Bachelor of Science: Physics. Poor math background, still doable?


How does "curved space" explain gravitational attraction?


Why do we have an elementary charge but no elementary mass?


Where does the 10 km of neutrons stars comes from?


How do we know that Quantum Mechanics isn't simply a theory of approximations?

How do we know that there isn't a classical solution to the measurement problem/Quantum Mechanical uncertainty?


What is the speed of one photon of a beam of light with respect to the other photon of the same beam?

Does a photon in vacuum have a rest frame?


How is Liouville's theorem compatible with the Second Law?


How to calculate the life expectancy / fusion rateof a star?

Predicting stellar evolution and life cycle of a star


How can a torque on a mass push it forward?

If I push or hit an object in space will it rotate or move along a straight line?


Statement of the first law of motion and definition of force

How does Newton's first law asserts the existence of inertial frames?


Someone walking on near side vs. far side of Moon - are weights different?

Are we slightly lighter during the day and slightly heavier at night, owing to the force of the Sun's gravity?


Radial length contraction in general relativity


How can a truly elementary particle decay into other particles?

Why do physicists think that the electron is an elementary particle?


Why can't we see light travelling from point A to B?


Terminal velocity of a settling sphere in 2D vs 3D


What is the minimum set of hypotheses which the present physics is based on?

Hilbert, Gödel, and "God equations" - a 19th century lesson for 21st century physicists?


Light was known to be a wave but had to be considered as made up of lumps not waves to explain ultraviolet catastrophe. Why?

Why does energy have to be emitted in quanta?


Has anyone mathematically proven the existence of Hawking Radiation yet?


Why must a fundamental particle's spin be a multiple of $\frac 1 2$?


Electric Field Topology in a Wire - Exact Duplicate


Why don't neutron stars transform into proton stars as a result of neutron beta decay?

What stabilizes neutrons against beta decay in a neutron star?


Black Bodies, why is $\nu_{max}\neq {c}/\lambda_{max}$?


What is actually a 'Field' in Physics? How can something affect something at a distance?


Why can quantum tunnelling be handled as a static problem?

Why can we treat quantum scattering problems as time-independent?


How can we assert $\mathrm{ matter } / \mathrm{ antimatter } \gg 1$ further than $locally$?


Best book on the theory of Standard Model of particle physics?

Books for particle physics and the Standard Model


If traveling at speed $c$ in space, we would be resting in the "time" dimension?

Would time freeze if you could travel at the speed of light?


What is so soft about soft symmetry breaking?

What does "soft" in "soft symmetry breaking" mean?


If I have a battery, and I connect two very long cables to it, with their ends separated, will I feel the current as soon as I touch both ends?


Can I say that two different quantities are zero?


Why is a quantum state described by a complex vector in the Hilbert space?

About the complex nature of the wave function?


Variational Derivation of Schrodinger Equation


Expansion in $\epsilon$ and $v^2$ dependence of the Lagrangian - Landau & Lifshitz's Mechanics

Deriving the Lagrangian for a free particle


How can black hole get mass if nothing can pass its event horizon?

How can anything ever fall into a black hole as seen from an outside observer?


So Black Holes Actually Merge! In 1/5th of a Second - How?


Finding Dirac Hamiltonian from Dirac equation


Doesn't the slowing of time when travelling at almost light speed create a paradox with an observer?

What is the proper way to explain the twin paradox?


Could wave-particle duality not be duality, but a constant switching between particulate and waveform?

Is the wave-particle duality a real duality?


Why aren't we sure that photons and gravitons are massless?


Is the normal force equal to weight if we take the rotation of Earth into account?

Why don't we consider centrifugal force on a mass placed on earth?


Difference in physical meaning between $\vec{D}$ and $\vec{E}$

Difference between electric field $\mathbf E$ and electric displacement field $\mathbf D$


Could we build a spherical shell around a black hole singularity inside the event horizon?

Fighting a black hole: Could a strong spherical shell inside an event horizon resist falling in to the singularity?


Which is the correct triangle to draw to derive the force component along a rope?

Why are triangles drawn like so when working with gravity on an inclined plane?


Where to start on learning Special Theory of Relativity?

What are the prerequisites to studying general relativity?


Does spacetime curvature (for time dilation) cancel out at the point of center of mass (because curvature effects cancel out from all directions)?

What is the general relativity explanation for why objects at the center of the Earth are weightless?


When a particle keeps "accelerating" near the speed of light, is the energy gained expressed in linearly gained impulse, or relativistic mass?

Why is there a controversy on whether mass increases with speed?


What happens to the absorbed colour on an object?

What happens to photons after they hit objects?


What's the number of significant digits for error bars?


$\zeta(-1)=\frac{-1}{12}\nRightarrow \sum_\limits{i=1}^\infty i=\frac{-1}{12}$ so how do we justify its use in string theory?

Critical Dimension of Bosonic Strings and Regularization of $\sum_{n=1}^\infty n$


Can someone explain effects of time dilation on expansion of universe


How can a photon have no mass and still travel at the speed of light?


How to check whether a given $W(x,p)$ represents a Wigner function of a physical state?

Necessary and sufficient conditions for a function to be the Wigner function of state


Why isn't Higgs coupling considered a fifth fundamental force?


Derivation of formula of potential energy by a conservative force

Force as gradient of scalar potential energy


What did Einstein mean by-matter curves and warps spacetime?

Physically what does warping (of space-time) mean?


Why doesn"t centrifugal force throw us off the earth?

Why don't we consider centrifugal force on a mass placed on earth?


Do calculations support the idea that our universe should be a black hole?


What limits the maximum sustainable surface charge density of a sphere in space?


Nonzero ground state energy of the quantum harmonic oscillator

Why not drop $\hbar\omega/2$ from the quantum harmonic oscillator energy?


Confused about the concept of time and time dilation

Is gravitational time dilation different from other forms of time dilation?


Is the shorthand $ \partial_{\mu} $ strictly a partial derivative in field theory?


Relating Quantum Mechanics to Classic Electromagnetism

How do you go from quantum electrodynamics to Maxwell's equations?


If sound travels through matter what medium does light travel through?

Why don't electromagnetic waves require a medium?


How is a vacuum able to propagate light?


Why is gravitational potential energy negative?

Why is gravitational potential energy negative, and what does that mean?


Problem books like I.E. Irodov for advanced physics


Mathematical books to become a successful mathematical physicists


Why the statement "there exist at least one bound state for negative/attractive potential" doesn't hold for 3D case?


Is it reasonable and common to interpret $dt$ as a time point (a point in time)?

Difference between $\Delta$, $d$ and $\delta$


Where does the polarity of particles come from?

Why do electron and proton have the same but opposite electric charge?


Given Newton's third law, why are things capable of moving?


Due to TIME stopping, are contemporary Black Holes really just Large SHELLS of Matter and not Singularities?

Can black holes form in a finite amount of time?


Optics simulation software for iypt #12 question thick lens


When talking about atomic mass, how is $E=mc^2$ factored in?

Why is there a controversy on whether mass increases with speed?


Gravitational lensing of massless photons


Mathematical bases/prerequisites for Feynman's "QED"


How do I prove that the Riemann curvature tensor is indeed a tensor?

How to check if a tensor transform a tensor?


Could dark matter be made of black holes?


How is dark energy consistent with conservation of mass and energy?


How does one experimentally determine chirality, helicity, spin and angular momentum of a fundamental particle?


Isn't Newton's Second "Law" merely a definition of force?

Are Newton's "laws" of motion laws or definitions of force and mass?


How to combine measurement error with statistic error


What prevents an orbiting object from getting a speed which is greater than $c$?

Rotate a long bar in space and get close to (or even beyond) the speed of light $c$


Define Pressure at A point. Why is it a Scalar?


Why does the (relativistic) mass of an object increase when its speed approaches that of light?


Calculate the average temperature needed for hydrogen fusion reaction

What is the lowest possible theoretical temperature that nuclear fusion can occur at?


Is there an analogue of a geodesic for the evolution of the electromagnetic field?


What are virtual objects, Reflection of light?


Are gravitons bound by the event horizon?


Would we be able to hear the sun if space were full of air?


The Physical Meaning behind a Commutator

What is the Physical Meaning of Commutation of Two Operators?


Nuclear decay - what happens to the electron shells?

What Happens to electrons after Alpha Decay and Nuclear Fission?


Breaking the speed of light relative to a moving object


Is the principle of least action a boundary value or initial condition problem?


Why is $M\frac{dv}{dt} = v_{rel} .\frac{dm}{dt}$ correct and $(M - dm)\frac{dv}{dt} = v_{rel} .\frac{dm}{dt}$ wrong?


Why doesn't our body gets crushed due to the atmospheric pressure?

Why the pressure of atmosphere doesn't crush you when you e.g. walk outside?


How Planck's quantum theory of energy solved the ultraviolet catastrophe?

How does quantization solve the ultraviolet catastrophe?


Functional integral aproach for Feynman rules

Quantum mechanics textbooks that use path integrals


General relativity && quantum mechanics "incompatibillity"

A list of inconveniences between quantum mechanics and (general) relativity?


What are the general solutions to a hard sphere collision?


What's the proper interpretation of canceling infinitesimals?


What does really mean by- power of a number or an exponential function is dimensionless?

Fundamental question about dimensional analysis


Relativistic addition of velocities of spaceships

If I run along the aisle of a bus traveling at (almost) the speed of light, can I travel faster than the speed of light?


Question regarding the mass of an alpha particle when travelling at a speed approaching the speed of light

Does the (relativistic) mass change? Why?


Textbook for mathematical Lagrangian mechanics

Classical mechanics without coordinates book


Twins Paradox - Does ageing depend on motion?


How to demonstrate that Fierz-like identity for 2-components Weyl spinors?

Representation under which Pauli matrices transform


Why is paper more frangible when it is wet?


What is the relation between Nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR)?

What's the difference between NMR and EPR?


Are gravitational waves constrained by special relativity (speed of light)?


Origin of Hamilton's variational principle

Is there a proof from the first principle that the Lagrangian L = T - V?


What exactly is entropy? Why is it measure of randomness?

How is $\frac{dQ}{T}$ measure of randomness of system?


What is the real meaning of mass in quantum mechanics?

The interpretation of mass in quantum field theories


What if there are two paths of least time?

Can there be multiple paths for which Fermat's least time principle can be obeyed?


How would I go about detecting monopoles?


Why is the speed of light constant in all inertial frames?

Why and how is the speed of light in vacuum constant, i.e., independent of reference frame?


When does light act as a particle and when as a wave?

Which side of wave-particle duality to choose in a given situation


What does it mean for two objects to "touch"?


ALL "forces" as manifestations of properties of space-time


If the universe is expanding, what is it expanding into?


Is entropy increase in disorder or 'energy-dispersal'?

Clear up confusion about the meaning of entropy


Hammer will fall faster than the feather on the moon. 10 second thought experiment!

Don't heavier objects actually fall faster because they exert their own gravity?


do gravity shows its effect in atomic level?

Has gravity ever been experimentally measured between two atoms?


How do electrons move across depletion region in npn transistor?

How does current flow from the emitter, through the base and to the collector in a NPN transistor?


Will the flash light accelerate in space?

If I'm floating in space and I turn on a flashlight, will I accelerate?


What is the mechanism of the semi-transparent glass?


Are quantum computers just massively parallel computers?

Can a parallel computer simulate a quantum computer? Is BQP inside NP?


Time as a Hermitian operator in quantum mechanics


How is conservation of momentum preserved in antimatter annihilation?

4-Momentum conservation for particle annihilation


Why was there frost on the inside of my windshield?

Why did my windshield freeze instantaneously?


Why do harmonics occur when you pluck a string?


Is it correct to say that different acceleration of free fall at the poles and equator is due to centripetal acceleration?

Why is Earth's gravity stronger at the poles?


How can light speed be measured relatively?

What is the relative speed of two near-light speed particles headed towards each other?


A problem with how curved spacetime explains gravity

How does "curved space" explain gravitational attraction?


What is the difference between weight and mass?


Book with problem sets that will go well with Dennery and Krzywicki's Mathematics for Physicists?

Mathematical physics text with plenty of applications


How is the total energy invariant under the addition of a total derivative?

Ambiguities in the energy-momentum tensor


Potential at a point is the work done to bring unit charge from infinity to that point

Why is the work done on a charge calculated from infinity?


Is the energy of the electromagnetic wave proportional to the amplitude or to the amplitude squared of the wave?

The relationship between the energy and amplitude of a wave? Derivation?


What causes certain spinning tops to flip?

Intuitive Explanation of Tippe Top Effect?


How can I self-teach myself classical mechanics?

Recommendations for good Newtonian mechanics and kinematics books


Why force applied which is equal to weight of an object is able to lift the object?

Why do objects move when you apply a force that's equal in magnitude to the friction?


What is the air resistance for objects moving supersonically?


My interpretation of conservation of angular momentum - is it correct?

Rotational kinetic energy when moment of inertia is changed


Can we think of the proof of local flatness theorem as the proof the the Einstein's Equivalence principle?

Curved space-time VS change of coordinates in Minkowski space


Does the angular momentum always point along the axis of rotation for rotation of a rigid body about an arbitrary axis?

Can the direction of angular momentum and angular velocity differ?


If time travel possible then we able to travel to future or past

Is time travel possible? Is it possible to go back in time?


Why does this consider the center of mass instead of the end? (RIGID BODY MOTION)


I have a somewhat silly question about pressure and atmosphere


How can black holes have infinitely small mass?

Is it possible to have a singularity with zero mass?


Good book on quantum field theory to start learning as an undergraduate?

A No-Nonsense Introduction to Quantum Field Theory


Are wormholes really a valid shortcut to distant points in the universe?


What is the logic that leads to conservation of energy from time invariance?

Noether Theorem and Energy conservation in classical mechanics


Is it possible that the speed of light has changed since the beginning of the universe?

Has the speed of light changed over time?


How is gamma ray blocked in the atmosphere in cosmic rays?

How Earth protected from the gamma rays generated by Sun?


Is there any thing composed of elementary particles in this world that is not 3 dimensional?


How can Wi-Fi bend through windows or penetrate walls?

If both radio waves and gamma rays can travel through walls


Huygens' Principle During Reflection: comparing wavelets from before reflection with wavelets from during reflection


Mathematically show that Quantum Mechanics and General Relativity are inconsistent

Can the problem of unification of Quantum Mechanics and General Relativity be converted into a pure Mathematical problem?


Gravitational time dilation at the earth's center


Why is friction proportional to normal force?

How is frictional force dependent on normal reaction?


What causes the dark bands in water wave ripples?

Why does the light at the bottom of the pool form this awesome pattern?


Is it true the Michio Kaku has completed a unified field theory started by Einstein by making use of string theory?


Is time unbounded in the future direction?

The universe appears to have a lower bound in the time dimension, why not an upper bound?


Does quantum entanglement really send a message?

Does entanglement not immediately contradict the theory of special relativity?


The equivalent resistance betweeen A and B. I need the answer with proper explaination


Is there a center of charge in a system in the same way as there is center of mass?


How come gas molecules don't settle down?


How to calculate the mass of the orbiting body given only its orbital information


Why doesn't this magnetic perpetual motion machine work?


Where does the component of the centripetal force in circular motion come from?

If the ground's normal force cancels gravity, how does a person keep rotating with the Earth?


Will an object orbiting a non-rotating mass with a layer of water on it cause two bulges of water on opposite sides of it?

Does Earth really have two high-tide bulges on opposite sides?


Why is acceleration due to gravity a constant?

Is acceleration due to gravity constant?


Resistance of a conductor shaped like a ball


Why isn't energy created by the superposition of waves?


Energy cancellation during superposition, why not? String waves

Why do travelling waves continue after amplitude sum = 0?


How can the rest-frame spectrum of redshifted light be determined?

How is Doppler redshift of distant galaxies established?


If a black hole is made by a hypothetical particle above Planck mass and it has angular momentum will it be a ring Kerr black hole?

Does quantum spin contribute to the angular momentum of a black hole?


Why is ampere defined with $2 . 10^{-7}$?


Why $(x-vt)^2$ does not represent a wave?

Why should a solution to the wave equation be finite?


Why is the potential difference across a component not constant?

The Difference Between voltage and current


Why do same/opposite electric charges repel/attract each other, respectively?


Feynman's Path Integral Approach: The Complex Exponentiated Action

Why is the contribution of a path in Feynmans path integral formalism $\sim e^{(i/\hbar)S[x(t)]}$?


Would two identical universes evolve identically?

Is the universe fundamentally deterministic?


What did we learn by detecting a gravitational wave?

Why is the detection of gravitational waves so significant?


Why do different color of the same materal differ temperature in the same sunlight?


Is it possible to have light without heat?


Simple harmonic motion in a horizontally accelerating lift

Time period of a pendulum when a constant horizontal force acts


How can LIGO's measures be unequivocaly tied to gravitational waves?

Are the LIGO observations proof of a black hole merger, and what happened to the black holes?


Why does gravity have such an insignificant effect on particles at an atomic scale?

Why is gravity weak at the quantum level?


If dark energy is responsible for the expansion of the universe, is it possible that it is also the force which creates dark matter?


Why does the Moon not revolve around the Sun directly?


Car Crash Question... (Conservation of Momentum?)

Is two cars colliding at 25 mph the same as one car colliding into a wall at 50 mph in reference to injuries?


Velocity from the cumulative distribution function of the Boltzmann distribution

Velocity Maxwell-Boltzmann distribution for dummies


Torque on rotating rigid body and pivot point

Component of angular momentum perpendicular to the rotation axis in rigid body rotation


Do relativistic frames imply different realities?

If a mass moves close to the speed of light, does it turn into a black hole?


How exact does the wavelength of light have to be to be absorbed by an atom?

How precise must the energies match for absorption of photons?


Why the force is inversly proportional to the square of distance?

Why are so many forces explainable using inverse squares when space is three dimensional?


Can we detect gravitational waves generated from inside the event horizon of a black hole?


Incomprehensible substance: information traveling faster than light?

Is it possible for information to be transmitted faster than light by using a rigid pole?


Physical reasons for metric definition in special relativity


Frequency or Wavenlenght; which changes when light is passing from rarer to denser medium?

Why does wavelength change as light enters a different medium?


Confusion in understanding of quantum fluctuations and vacuum energy

Are vacuum fluctuations really happening all the time?


Why are the dineutron and diproton unbound?


Do photons generate gravitational waves since they affect with their energy the stress tensor?

Do photons and cosmic rays radiate energy through gravitational waves? If not, why not?


Could planets survive their star becoming a black hole?

What is the safe distance to a supernova explosion?


Is torque necessary in rigid body mechanics?

Can torque relations actually be *derived* from Newton's Laws, or is it something extra?


Thought experiment about wavelength of light through a medium

Why doesn't the frequency of light change during refraction?


Could these hypothetical very long distance properties of light offer alternatives to an expanding universe or a finite number of galaxies?

Is it possible that galaxies' redshift is caused by something else than the expansion of space?


Other explanation for cosmological redshift?


When the external resistor increases in temperature, why is the calculated value for internal resistance higher?


Michelson interferometr electromagnetic wave formula

What is the physical significance of the imaginary part when plane waves are represented as $e^{i(kx-\omega t)}$?


How would behave theoretical matter with negative mass?


A curious case of Relativistic Velocity Addition


Argument for proving that the universe must be indeterministic

Is the universe fundamentally deterministic?


Why do liquids boil when their vapor pressure equals the ambient pressure?


What in Newton's three laws of motion is original and not a paraphrasing of his predecessors?


Gravity and Magnetism... One and the same?

Is gravity just electromagnetic attraction?


Introduction of the vector potential $A_{\mu}$ for the local gauge invariance of the complex scalar field lagrangian


Is energy expended when a force is exerted on a object?

Why does holding something up cost energy while no work is being done?


Why does no physical energy-momentum tensor exist for the gravitational field?


How are objects able to move even after newton's third law of motion

Given Newton's third law, why are things capable of moving?


How can I prove/understand the following functional derivative?

Inverse Green's Function identity in derivation of Hedin's equations


Speed of light in vacuum in non-inertial frame

Does the speed of light vary in non-inertial frames?


Why should there be electrostatic equilibrium inside a conductor?

In electrostatics, why the electric field inside a conductor is zero?


Does the weight of a steel ball changes when submerged in water?

Does a non-buoyant (denser than water) object (such as a lead diving weight) weigh any less when submerged in water?


Difficulties in understanding basic energy equation in quantum mechanics

$\lambda=\frac{2h}{p}$ instead of $\lambda=\frac{h}{p}$?


Do satellites need to have their orbits externally maintained?

What is the typical orbital life of an artificial satellite?


charge given to parallel conducting plates

Why are the two outer charge densities on a system of parallel charged plates identical?


Squaring the E&M (Maxwell) field strength tensor

Expanding electromagnetic field Lagrangian in terms of gauge field


Is there a historical name for an inductor that starts with the letter $L$? (RL circuits)


Physical meaning of magnetic vector potential

How to interpret the magnetic vector potential?


Can an astronaut in free space turn his head without moving the rest of his body in opposite direction?

Is there a way for an astronaut to rotate?


Can You Obtain New Physics from the use of Fractional Derivatives?


Refractive index and wavelength relation

Does the wavelength always decrease in a medium?


Why can't we give photon mass in vacuum?


If I push or hit an object in space will it rotate or move along a straight line?


How does gravity change nearing the core in free fall?

If it was possible to dig a hole that went from one side of the Earth to the other...


Why is that? repulsive forces and attractive forces

Is it correct to use Bernoulli's theorem to explain that a disk floats in the air? Should the correct explanation be based on Boyle's law?


Is Randall Munroe's "what-if" xkcd correct that magnified moonlight can't get things hotter than the moon?

Is it possible to start fire using moonlight?


What is the proper way to explain the twin paradox?


Photon energy depends on frequency (and/or amplitude)?

Amplitude of an electromagnetic wave containing a single photon


What exactly makes a force conservative?


How does the drift velocity of electrons in a conductor depend on the temperature?


Operational definitions in Newtonian Physics


Why do all fluid particles crossing a point in a steadily flowing fluid have to follow the same path?

Can two streamlines in a fluid be tangential to each other not crossing each other?


What is the difference between a white object and a mirror?


Why doesn't a bird on an electric line get electrocuted? KVPY 2017

Why do birds sitting on electric wires not get shocked?


How likely is it that the mass of all humans was generated by the same supernova?

How many times has the matter in our solar system been recycled from previous stars?


Solution for inverse square potential in $d=3$ spatial dimensions in quantum mechanics

Radial Schrodinger equation with inverse power law potential


Is it physically possible for gravity to accelerate an object with mass to the speed of light?

Will an object always fall at an infinite speed in a black hole?


More work done at a higher velocity with the same force?

What is force? How does a constant force output a nonconstant power?


How does current flow in a conductor if the electric field in a conductor is always 0?

Is there no electric field inside a conductor?


Direction of Friction Force of a box on a moving truck ( question is different and not as advanced, focused on a situation )


How can an electromagnetic wave propagate on itself even if there is no source that has created it?


Why light cannot pass through wall whereas Sound can?

Why can't light pass through walls but sound can?


Quantum Entanglement, connected or just in tune?

Quantum Entanglement - What's the big deal?


How can a photon have no mass and still travel at the speed of light?


Internal energy for a diatomic gas that undergoes an adiabatic process?


Why "Dark Energy" is called energy instead of force?


Does gravity exert more "power" when an object is traveling faster?

Is kinetic energy a relative quantity? Will it make inconsistent equations when applying it to the conservation of energy equations?


Is the electromagnetic spectrum discrete?


'Push' in a rigid rod travel at speed of sound or speed of light

Is it possible for information to be transmitted faster than light by using a rigid pole?


What is the interstellar density of mm sized "dust" particles?


Travel duration from Earth to a star at 9.8 m/s² acceleration

How long would it take me to travel to a distant star?


Why are magnetic fields only produced by moving charges?

How do moving charges produce magnetic fields?


Is it possible to have a magnet which looks like a hollow cylinder and who's north is interior and south is exterior?

What is the magnetic field inside hollow ball of magnets?


Total time taken for an accelerating frame in special relativity


How do gravitons impact on general relativity?

How can gravitions exist without violating GR?


Why are electrons defined to have negative charge?

Why is the charge naming convention wrong?


Distance in relativistic circular motion in invariant spacetime


Why does blowing on someone who is wet feel colder than on someone who is dry?


What is Verlinde's statistical description of gravity as an entropic force?

What is Mathematical formulation of entropic Gravitational force?


Is it possible to derive the invariant spacetime interval from Einstein's two postulates for SR?

Einstein's postulates $\leftrightarrow$ Minkowski space for a Layman


What happens if you try to freeze water in an water tight container


How do we deal with irrationals in Physics?

Is it possible for a physical object to have an irrational length?


Would time freeze if you could travel at the speed of light?


What are the good introductory resources for M-theory towards AdS/CFT?


Can a single particle create a black hole?


How can I understand a Vortex Tube and its efficiency?


What are good examples to demonstrate Einstein's mass-energy relation


Should entropy have units and temperature in terms of energy?

Why isn't temperature measured in Joules?


Why does a balance try to be horizontal? The moments are equal

Why does the weighing balance restore when tilted and released


Observer inside event horizon of an extremely large black hole

Does someone falling into a black hole see the end of the universe?


Quarks in a hadron: where does the mass come from?


Why do many equations need squared powers?

Why do most formulas in physics have integer and rational exponents?


Given Newton's third law, why are things capable of moving?


Trouble understanding the Bohr model of the atom


What is the time of impact of a dropped item at a very high altitude

Time taken for object in space to fall to earth


How does Huygens Principle incorporate the unidirectional property of a traveling wave?


Speed of sound relative to density of medium through which sound travels


Electron's eternal "orbit" about the nucleus

Why don't electrons crash into the nuclei they "orbit"?


How do animal perceive distances with their eyes and ears


Could anyone explain to me how the products of nuclear fusion/fission are predicted?

Predict decay chain of a radioactive element


If the wave function of two identical fermions is antisymmetric, how can they be identical?

When are two fermions considered identical?


Does the Heisenberg uncertainty principle hold up for events in the past?

Is the Uncertainty Principle valid for information about the past?


Can we tell how far away is the source of gravitational wave from the chirp alone?

Is there a model relating GW signal and luminosity of the merger / burst?


We can see our face in a mirror, but why not clearly in a aluminium or steel?

Why can't we see images reflected on a piece of paper?


Total work done by friction on a system, when friction is static and internal to system?

What will be the total work done by friction on the system (man+boat)?