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?
High School Electric Flux - confused about integrating over a tilted area
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High School Calculating non-dielectric reflectance without using complex numbers
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Undergrad Gravity inside an exponential mass disk
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High School Why can't we calculate capacitive reactance like u/i?
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Undergrad How to develop the rocket equation?
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Undergrad Why isn't the Lagrangian invariant under ##\theta## rotations?
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Undergrad Doubling Ionization of Tungsten: Effects on Energy?
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Undergrad Understanding the propagation of sound on molecular Scale
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Graduate H-Theorem and Lagrange multipliers
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Undergrad Why most probable energy and speed do not correspond?
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Undergrad So what are the definitions of gas, liquid, solid?
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The SpaceX Launch and Aftermath
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Graduate Can the orientation of a body be defined by Euler angles?
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Graduate Understanding Free Expansion of Gas: Velocity Distribution Function Evolution
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High School Water surface behavior under pressure change
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Undergrad Realistic steering wheel angle when car follows points along a path
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High School To measure light's frequency, do we interact with each crest + trough?
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High School Pressure in a viscous liquid versus non-viscous fluids
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Undergrad Lagrangian approach for the inclined plane
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Undergrad Understanding Vectors: Magnitude & Direction
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High School Some Questions About Drag (for ships in water and airplanes in air)
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Undergrad Electrostatic force exerted on an electron inside a nucleus
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Undergrad Photoelectric effect: Saturation voltage
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Undergrad Tensor Calculus (Einstein notation)
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High School Does the inverse square law equalize gravity at different spots?
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Graduate Corresponding case of steady precession but for Tait-Bryan angles
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High School Should I use True North or Magnetic North to align my sundial?
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High School How Does the Electric Field of a Moving Charge Appear?
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Graduate Are equations of motion invariant under gauge transformations?
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Undergrad Can Air Resist a Piston? A Serious Discussion
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Undergrad Finding the Axis of Rotation with Given CoG and Force Point
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High School Homopolar motor rotation in Vacuum
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High School Model rocket physics: Why doesn't the motor go through the nose cone?
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Undergrad How do we calculate the energy we used to do something?
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High School Understanding air flow and resistance
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Graduate Euler, Tait-Bryan, Tait, proper, Improper
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High School How does the density of air affect the note you hear?
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Undergrad Car Accident Physics - Are Wheels/Tires Good or Bad Energy Absorbers?
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High School How does wind affect a turn for an aircraft?
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High School Troubleshooting Battery Internal Resistance Measurements
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High School Why use this premise behind the Maxwell-Boltzmann curve?
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High School Seeing both B field lines and E field lines at the same time
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Graduate Measurement uncertainty due to thermal noise
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Graduate Forces on rotating disk object
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Undergrad Neil DeGrasse Tyson on "sharing water" with historical figures
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High School How long does it take to reach harmful CO2 levels in a room?
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Graduate Mass dropped onto rotating disk
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Undergrad Rolling Motion direction of Velocity center of mass
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Graduate Virial theorem and translational invariance
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Undergrad How can engineers get away with splitting differentials in dynamics?
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High School Interpreting light as Maxwell's EM wave
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Undergrad Vector calculus: line element dr in cylindrical coordinates
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Undergrad Equalizing airflow through multi-hole orifices
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Undergrad How Can Two Waves with Different Amplitudes Be in Phase?
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High School What is meant by "upper limit of work done on Earth"?
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Undergrad Help with Euler Lagrange equations: neighboring curves of the extremum
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Why is Gravitational Force Proportional to Mass Product?
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High School How do I calculate the drop force on a cord and eye bolt?
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Undergrad Why does ##u## need to be small to represent the Taylor expansion
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Graduate Trig functions and the gyroscope
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Undergrad Transmission Line EM Wave vs EM Wave in Free Space
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Undergrad Surface area and length (percent increase relationship)
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Undergrad Moment of inertia and contact force
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Graduate Conservation Laws from Continuity Equations in Fluid Flow
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Undergrad Independence of Trace-Partition function
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High School Archimedes Principle - A Rock and Water Magic Trick
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Undergrad Magnets, Outer space, and Rings
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Graduate Determination of electron temperature in an ion source
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High School How do fields retain their uniformity with interposing objects?
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Undergrad At what level will the water settle in this system?
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High School Does Mass Matter in Free Fall?
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Undergrad Measuring Low Resistance: Why Meter Bridge is the Preferred Choice
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Undergrad Pickleball Physics -- Player reaction time vs aging
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Undergrad What is the benefit of measuring both direct and reverse current?
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Undergrad Thoughts about coupled harmonic oscillator system
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High School Negative pressure in a car to power it
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High School Is the Definition of Work Done Applicable to Free Fall?
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Graduate Euler vs. Tait (steady precession vs... what?)
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Graduate Radiation back reaction in classical electrodynamics
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Undergrad Contemplating Gyroscopic Forces for fighting robot weaponry
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High School Air tank PSI and cubic feet calculation help please
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Undergrad Equations for Spherical Resonators
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Undergrad Velocity of Buoyant Plug in Closed Loop
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Undergrad How does the mass of the wheels affect the car's acceleration?
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Undergrad Pressure Required to Circulate Liquid in a Closed System?
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Undergrad Is Information a conserved quantity or not?
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Undergrad Mercury as a plasma at 150 Kelvin
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Undergrad Amplitude of the maximums in single slit diffraction
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High School How Do Oscillations and Particles Interact in Electromagnetic Fields?
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Undergrad Is it possible, that one physics law is "Everything is in motion?"
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High School Hydrodynamics Effects: Are They the Same?
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Graduate Macroscopic field - seeking a thorough exposition
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Undergrad On whether the motion of a Foucault pendulum bob is comparable to ballistics
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Undergrad Wall material effect on Van der Waals gas?
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Undergrad Why is Cherenkov radiation blue? And what about refractive index?
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Undergrad Understanding Physical Processes: EM, Gravitational, Mechanical & Entropic
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Graduate Steady state confined flow field: Is it cyclic?
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Undergrad Don't Ever Mention "Centrifugal Force" to Physicists
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Finding the terminal velocity of a model rocket from a list of velocities
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Undergrad Just for fun: treadmill air conditioner efficiency calculation
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