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

High School Mousetrap Car Energy efficiency

Optics

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

Thermodynamics

Undergrad Using the "triple point of water" to produce ice -- How does that work?

Electromagnetism

Undergrad What determines if wave components are independent vs coherent?
Undergrad Axial angular momentum calculation
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Undergrad Why if net force=zero, moment at any point is same?
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423
High School Thought Experiment on Charge Carriers and Electrical Conduction
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312
Undergrad Question on derivation of a property of Poisson brackets
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Undergrad What is the pressure of trapped air inside this tube?
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High School Question about the color of a thin film
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Undergrad Reference frames, center of rotation, etc
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Undergrad How to quantify gyroscopic precession torque?
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Graduate Static Electricity foam balls
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298
High School Limiting case for an Atwood's machine
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516
High School Which technique has been used? (drowning victim recovery in a lake)
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Undergrad Does a Point Charge in Classical Electromagnetism Possess Self Energy?
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Undergrad What areas of maths and physics do I need to understand explosion physics?
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Undergrad Properties of angular momentum
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655
High School Trying to understand wind forces on a door
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581
High School Why higher speeds need more power if the backward force is the same?
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Undergrad Calculate acceleration from power/torque graphs
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High School How Does Constant Power Affect Rocket Acceleration in Space?
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511
Undergrad Confusion about derivation of equation in Gregory
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507
Undergrad Different Definitions of The Quality Factor
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515
Undergrad The rocket equation, one more time
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Undergrad Varying resistance readings depending on how I connect my meter
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Undergrad Does a person's mass affect time?
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Undergrad A question about the origin of Coulomb's law and point charge divergence
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800
Undergrad Instantaneous electric field solved by extended electrodynamics?
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510
High School 'splain this hydrostatic paradox in tiny words
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Undergrad Ampere-Maxwell law seems to contradict causality?
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595
Graduate Please Explain Elementary Physics Elevator Question
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796
Undergrad Explain Bernoulli at the molecular level?
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Undergrad Coulomb gauge implies instantaneous radial electric field?
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718
High School The Effect of Linear and Rotational Motion on Measured Weight
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665
Undergrad Simple thought experiment with Stefan-Boltzmann law: energy
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696
Undergrad Does Poisson's equation hold due to vector potential cancellation?
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612
Undergrad Griffith, Electrodynamics, 4th Edition, Example 4.8. (First part)
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784
High School A scenario of non-uniform circular motion
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503
Undergrad Gauss' law seems to imply instantaneous electric field propagation
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Undergrad Recovering Hamilton's Equations from Poisson brackets
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542
Undergrad Do electron density waves accompany EM waves in coaxial cables?
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570
High School Highway: Deriving speed from Doppler shift
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Undergrad To predict the nature of Normal Reaction in any mechanics set-up
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Graduate Advice for 100 MHz resonator
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786
Undergrad Off resonance driving of a MW/RF cavity
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620
High School What qualities does time have other than linearity, motion, and speed?
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597
High School Can Light Speed Be Increased by Straightening Its Wave Path?
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779
High School Question about pressure of a liquid
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771
High School Why is the 3 body problem unsolvable? And what will happen if someone solves it?
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Undergrad Relationship between nuclear magnetic physics and Maxwell's demon
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High School Why is displacement the integral of acceleration with respect to time? [corrected in thread]
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Undergrad Feynman's derivation of average square distance variation in Brownian motion
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Undergrad Deriving the conformal Laplacian
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High School Understanding Newton's Third Law and the Net Force on Objects
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High School Work done when moving an object
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High School Why Does a Spring Return to Its Original Position After Being Stretched?
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High School What is the Correct Reading on the Scale in This Mass/Scale Puzzle?
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High School Ultrasonic wave and regular sound wave
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Graduate When should I analyze optical problems using ray tracing vs. wavefront analysis?
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Undergrad Topic about physics axioms, theory, laws etc..
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High School Why Does Hooke's Law Use a Negative Sign in Scalar Form?
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Undergrad Is ##p^k = \partial L / \partial \dot{x}^k## true for all ##L##'s?
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Undergrad Shielding behavior of a steel cuboid in a DC magnetic field
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Undergrad Reframing Light Bending Using Density Instead of Radius
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Undergrad Intuitive look at bending of light by gravity
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Undergrad A "continous" gravitational field formula r=0 to infinity
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Undergrad Board Breaks: Small or Large Deflections?
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Undergrad Visualising rotation in 3-D space
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High School (Electric) current is not a vector quantity
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High School Use Surface-Volume to approximate gravity for planets and protons
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Undergrad Describe the Physics involved in swinging a rope to catch a cow
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High School An explosion under a pile of timber and rocks
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Undergrad Color and appearance of a "pile" of biological viruses
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Undergrad Boundary conditions for a wooden board used for breaking in martial arts
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Undergrad Explaining the magnetic (cable) paradox
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Undergrad Problem with light-ray construction
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Undergrad What does the Lattice Boltzmann Equation actually say?
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High School EMF induced by Bar Magnet falling through a Coil
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Undergrad Does kinetic friction propel a person walking forward?
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Undergrad Is Mechanical Energy Conservation Free of Ambiguity - follow up
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High School Slow Motion Appearance of Flags: Fluid Dynamics or Perceptual Illusion?
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High School Why do sails on a boat generate lift perpendicular to the sails?
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Undergrad Interception problem with curve (computer simulation)
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High School Problems with modelling the vertical motion of a dust particle
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High School Deacceleration causes object to move backwards?
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High School Question about Newton's 3rd law: Two boxes sliding toward each other and colliding
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Undergrad Air flow between sphere/cylinder and membrane
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High School The horizontal speed of an object does not affect the time it takes to fall vertically?
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High School What limits a rocket's max speed if in space drag is zero?
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Undergrad A thought about visualizing space-time
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High School Inertia of a rolling dumbell
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Undergrad Permeability of Metglas and Propagation Velocity
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High School Symbol for temperature on the Fahrenheit scale
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Is Velocity Increasing Below the X-Axis?
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Undergrad Bose-Einstein statistics for μ>ε
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Undergrad Problems with Blum's Karate Article
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Undergrad Are 1D Longitudinal Waves Reflected at an Open End?
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High School Temperature-Dependence of Viscosity of a Fluid?
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Undergrad Weird Depictions of Birefringence with Angle of Incidence 0°
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Undergrad Questions about Jean-Rayleigh's derivation of Ultraviolet Catastrophe
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High School How Did Scientists Develop and Validate the Atomic Model?
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First law of this universe
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High School Why Do Objects Bounce? Exploring Momentum and Energy Conservation
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