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

I Is calling fictitious forces "not real" just about terminology?

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 Reflections at the source point of a transmission line
B Gas Interaction in a Box: Force and Pressure Dynamics
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B Why doesn't the Earth at the equator experience a sonic boom?
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B Looking for an example.... (misalignment of the Apollo 11 rocket)
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A Ground Penetrating Radar formula
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I How to introduce dissipation to a spinning top
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B How to Compile a Report on Experiments: Resources & Tips
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B Gravitational force between two masses
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I Estimating Particle Number in an Electric Field
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I The Gyroscopic Effect: Precession, Nutation, & Boomerang Return
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B Where am I going wrong (energy transfer between black bodies)?
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B The Illusion of Anti-Gravity (aka a Superior Mirage)
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I Physics of exercising and forces felt
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A Lagrange with Higher Derivatives (Ostrogradsky instability)
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I Rail gun - point of application of force?
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I Feynman's reversible and irreversible machines
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B Does Combined Luminosity of LEDs Add Up?
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I How does the slanted mast track improve railing on a windsurf board?
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I Physics of sailing/windsurfing systems
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I Does the Normal contact force act through the centre of mass?
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B Question about Primary Colors -- Why Red-Green-Blue?
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I The kilogram and Planck’s constant
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I Why is my derivation of the catenary wrong?
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B Is there a formula to obtain the mass of a proton from c?
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I Euler, Calculus of Variations and Mast on a ship
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I Seesaw problem with a man connected to a fan by a rope
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I When can I treat a joint as a fixed conection?
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B Defining 1 Second: The History and Science Behind Time Measurement
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B How Does Phase Change Affect the Equation of a Stationary Wave?
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I Question regarding dh, du, cp, cv for ideal gases
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A Solution of Poisson's Equation
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A Derive Cattaneo–Vernotte Law w/Proof
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I Why is the 'motionless solution' not always valid in classical mechanics?
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I How Does Each Element in the Permittivity Tensor Matrix Represent an Anisotropic Material?
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I How Is Entropy Calculated in an Irreversible Gas Expansion?
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B Value of G Changing Over Time?
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B What are your favourite classical physics puzzles?
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B Why is Young's modulus constant below the limit of proportionality?
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A Calculating noise of a transducer from molecular vibration
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I What is the purpose of the Prandtl Mixing Length for turbulent flow?
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B Measuring a change in gravity - thought experiment question
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B What Is the Correct Calculation for Induced EMF in This Circuit Scenario?
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A How Does Jet Injection Work in Fluid Dynamics?
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B What is the Length of a Compound Microscope?
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B How do I know in which direction an object is moving?
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I Wavelength and size of holes or grating
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A Two disks -- An educational problem
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I Can Precession Explain the Stability of High-Speed Ice Skaters?
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I Unleashing Solar Energy: The Potential of Mirrored Circles and Solar Panels
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B Is Gravity Really a Force? A Look at General Relativity's Perspective
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I Can the Exact Boltzmann Distribution Yield Specific Quantum State Populations?
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B The physics explanation of ~bendy~ rays
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B Apparent missing negative phase oscillation energy - where is it?
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I Orbital maneuver by applying a thrust in the radial direction
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I How to stay warm lost in the wilderness in winter?
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I Help with Levi-Civita manipulation
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I Trying to get a physical understanding of a Fermi gas
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I Does Poynting's Theorem only involve external fields?
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I What is a good formula for the Laplace operator?
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B Variation of air density with height
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I Deriving Curl of B from Biot-Savart Law & Vector Identity
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A Is there a closed form solution to Kepler's problem?
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B Why is Gaussian charge not equivalent to SI charge?
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B Vacuum permittivty with alternative Standard-Unit for meters
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I The world from a bat's perspective (sonic images)
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B Mobility in a Strong Gravity Environment vs. Moving Mass?
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A Dx in an integral vs. differential forms
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I Variant and Invariant Physical Quantities....
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I How Does the Position of a Free Vector Couple Affect Its Behavior?
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B Understanding the Change of Variables in the Hannay Angle Proof
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B Dot Products -- Some questions to help my understanding
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I Where Can I Find Germanium PIN Photodiodes for Sale?
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I How viscous forces affect force transmission in hydraulic systems.
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B Implicit error margins based on significant figures
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I Why is it claimed that Betz's limit is a law?
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I Gibbs paradox: an urban legend in statistical physics
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I What happens if you increase μ0 and decrease ϵ0? Or vice versa
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I Units of trigonometric functions?
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B Explore the Hypothetical: What Happens to a Spinning Top with No Forces?
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A Solving Kepler's Equation Over Three Centuries
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Discovering Drum Head Patterns for Music Education
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A Parametric Lagrangian is a Homogeneous Form in Parametric Velocities?
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B Clashing approximations for this precession problem
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I Steady precession of a gyroscope
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B Photo of crosswalk lines distorted by tires action-reaction
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I Disappearing Sun: A Thought Experiment on the Effects of Gravity and Light
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I Can Joule-Thomson effect freeze air?
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B Length is the measure of intervals in space?
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I Spacetime invariance algebraic proof
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I Symmetry and Finite Coupled Oscillators
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B A bit confused about this variation
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I UV mercury lamps: Changing the 185nm vs 253.7nm ratio
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I Kinesculpture Stopping: Is It Physics or Complaints?
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I Why is action considered a scalar in physics?
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I What happens when two waves in counter phase affect a conductive material?
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I Which version of the Kepler Problem is correct?
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I Stratification of air in a closed system vs the stack effect
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B Does the Order of insulating layers matter?
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B Does Gravity decrease at a steady rate as we go away from the Earth?
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B Event horizon for observer within main horizon
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B How to Linearize an R vs θ graph (distance vs angle)
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