Classical Physics Forum

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Join expert classical physics discussion on the principles developed before the rise of relativity and quantum mechanics. Including mechanics, electrodynamics, thermodynamics, optics.

Mechanics

B Applied Mechanics -- Billiard Balls

Optics

I How do I stretch a laser from a beam into a sheet?

Thermodynamics

I What thermal cycle would describe the action of a candle carousel?

Electromagnetism

A 3D rendering of electric field lines of a swiftly moving charge
B Trying to understand wind forces on a door
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B Why higher speeds need more power if backward force is the same?
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I Calculate acceleration from power/torque graphs
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B Rockets and power
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I Confusion about derivation of equation in Gregory
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I Different Definitions of The Quality Factor
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I The rocket equation, one more time
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I Self Energy?
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I Varying resistance readings depending on how I connect my meter
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I Does a person's mass affect time?
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I A question about the origin of Coulomb's law and point charge divergence
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I Instantaneous electric field solved by extended electrodynamics?
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B 'splain this hydrostatic paradox in tiny words
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I Ampere-Maxwell law seems to contradict causality?
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A Please Explain Elementary Physics Elevator Question
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I Explain Bernoulli at the molecular level?
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I Coulomb gauge implies instantaneous radial electric field?
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B The Effect of Linear and Rotational Motion on Measured Weight
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I Simple thought experiment with Stefan-Boltzmann law: energy
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I Does Poisson's equation hold due to vector potential cancellation?
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I Griffith, Electrodynamics, 4th Edition, Example 4.8. (First part)
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B A scenario of non-uniform circular motion
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I Gauss' law seems to imply instantaneous electric field propagation
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I Recovering Hamilton's Equations from Poisson brackets
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I Do electron density waves accompany EM waves in coaxial cables?
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B Highway: Deriving speed from Doppler shift
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I To predict the nature of Normal Reaction in any mechanics set-up
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I What areas of maths and physics do I need to understand explosion physics?
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A Advice for 100 MHz resonator
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I Off resonance driving of a MW/RF cavity
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B What qualities does time have other than linearity, motion, and speed?
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B Can Light Speed Be Increased by Straightening Its Wave Path?
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B Question about pressure of a liquid
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B Why is the 3 body problem unsolvable? And what will happen if someone solves it?
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I Relationship between nuclear magnetic physics and Maxwell's demon
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B Why is displacement the integral of acceleration with respect to time? [corrected in thread]
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I Feynman's derivation of average square distance variation in Brownian motion
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I Deriving the conformal Laplacian
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B Understanding Newton's Third Law and the Net Force on Objects
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B Work done when moving an object
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B Why Does a Spring Return to Its Original Position After Being Stretched?
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B What is the Correct Reading on the Scale in This Mass/Scale Puzzle?
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B Ultrasonic wave and regular sound wave
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A When should I analyze optical problems using ray tracing vs. wavefront analysis?
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I Topic about physics axioms, theory, laws etc..
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B Why Does Hooke's Law Use a Negative Sign in Scalar Form?
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I Is ##p^k = \partial L / \partial \dot{x}^k## true for all ##L##'s?
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B Which technique has been used? (drowning victim recovery in a lake)
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I Shielding behavior of a steel cuboid in a DC magnetic field
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I Reframing Light Bending Using Density Instead of Radius
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I Intuitive look at bending of light by gravity
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I A "continous" gravitational field formula r=0 to infinity
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I Board Breaks: Small or Large Deflections?
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I Visualising rotation in 3-D space
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B (Electric) current is not a vector quantity
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B Use Surface-Volume to approximate gravity for planets and protons
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I Describe the Physics involved in swinging a rope to catch a cow
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B An explosion under a pile of timber and rocks
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I Color and appearance of a "pile" of biological viruses
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I Boundary conditions for a wooden board used for breaking in martial arts
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I Explaining the magnetic (cable) paradox
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I Problem with light-ray construction
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I What does the Lattice Boltzmann Equation actually say?
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B EMF induced by Bar Magnet falling through a Coil
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I Does kinetic friction propel a person walking forward?
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I Is Mechanical Energy Conservation Free of Ambiguity - follow up
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B Slow Motion Appearance of Flags: Fluid Dynamics or Perceptual Illusion?
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B Why do sails on a boat generate lift perpendicular to the sails?
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I Interception problem with curve (computer simulation)
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B Problems with modelling the vertical motion of a dust particle
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B Deacceleration causes object to move backwards?
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B Question about Newton's 3rd law: Two boxes sliding toward each other and colliding
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I Air flow between sphere/cylinder and membrane
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B The horizontal speed of an object does not affect the time it takes to fall vertically?
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B What limits a rocket's max speed if in space drag is zero?
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I A thought about visualizing space-time
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B Inertia of a rolling dumbell
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I Permeability of Metglas and Propagation Velocity
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B Symbol for temperature on the Fahrenheit scale
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Is Velocity Increasing Below the X-Axis?
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I Bose-Einstein statistics for μ>ε
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I Problems with Blum's Karate Article
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I Are 1D Longitudinal Waves Reflected at an Open End?
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B Temperature-Dependence of Viscosity of a Fluid?
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I Weird Depictions of Birefringence with Angle of Incidence 0°
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I Questions about Jean-Rayleigh's derivation of Ultraviolet Catastrophe
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B How Did Scientists Develop and Validate the Atomic Model?
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First law of this universe
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B Why Do Objects Bounce? Exploring Momentum and Energy Conservation
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B How to use magnets in levitation?
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B Would there be any varying forces acting on individual wells in rotation? (stir/shaker plate)
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I Is there action at a distance at the atomic level in physics?
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I Two kinds of pressure
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I Creating White LEDs: Phosphor vs RGB
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B Doubt regarding relative acceleration
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I Solving a momentum problem where masses change after the collision
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B Not sure about the magnetic flux (phi) depending on a cosine function
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B Is water pressure on an inclined wall less than the weight of the water?
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A Flaw in Lagrangian Mechanics for a rotary inverted pendulum system? (Simulation vs. Measured)
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B Electric Field Direction: Are We Assuming a Universal Positive Frame?
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