Unanswered Questions
1,541 questions with no upvoted or accepted answers
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How to compute classical probability distribution for 1D harmonic oscillator with $K/x$ (central force) potential energy?
I am trying to find, or derive, the probability distribution function for a classical 1D harmonic oscillator with a $K/x$ potential energy (from a $K/x^2$ central force). I am familiar with the ...
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Overlap of Liouville densities
I am having a little trouble understanding the meaning of the fact that the convolution of two Liouville densities $\rho_{1}(p,q,t)$ and $\rho_{2}(p,q,t)$ (i.e. the classical probability overlap) ...
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Collisions with Spheres (with Different radii) on a plane
How do you calculate the new velocity of the spheres after a collision when the spheres have different radii?
I thought you could just decompose the horizontal velocities and use the standard ...
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Precession of a closed orbit under a central force other than the inverse square force
Consider the motion of a closed orbit in a central force field ${\bf F}({\bf r})$ other than the inverse square force i.e., $${\bf F}({\bf r})\neq -\frac{k}{r^2}\hat{\bf r}.$$
However, since ${\bf F}({...
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Quantum-Classical Hybrid theories: How useful are they?
I have seen several attempts at building a consistent quantum-classical theory, i.e., a theory where a quantum (sub) system interacts with a classical one somehow.
Examples: (1) https://iopscience.iop....
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D'Alemberts Principle to solve a Classical Mechanics problem
I found this question on this very site and was curious on how to solve it using D'Alembert's Principle
.I already know how to do it by balancing the torque about toppling point so please don't post ...
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Materials that behave as "metals" for sound waves?
Probably the most well known property of metals are that they are shiny. Ultimately arising from the high density of conduction electrons capable of carrying current, this shinyness is means that ...
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Is there a unique accepted Lagrangian formulation of Nambu mechanics?
In section 5 of their 2000 paper "Nambu Mechanics in the Lagrangian Formalism", Ogawa & Sagae critique previous attempts by Bayen & Flato and by Takhtajan to formulate the theory ...
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Why does the photon in Compton Scattering have a minimum frequency/maximum wavelenght?
Using conservation of four-momentum one finds that, with respect to the angle of deviation of the photon from its original direction $\theta$, the wavelength and frequency of the emitted photon are:
$
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Locating point of impact "during" elastic collision (1D)!
We have two objects moving opposite to each other on the x-axis. They started to collide on the location $x = 0$ on x-axis.
We know that if object one $m_1 = 10 kg$, and $v_1 = 10 m/s$, and object ...
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Physical interpretation of the definition of angular momentum in classical mechanics
To what I understand, the following is a valid way to introduce the angular momentum $\mathbf L$ in the Lagrangian system of a rigid body. We can consider the extended configuration space to be $M\...
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The idea of scattering cross-section in classical mechanics, quantum mechanics, and high energy physics
I am very confused about the idea of the cross-section in classical mechanics, quantum mechanics, and high energy physics. It seems like in classical and quantum mechanics, scattering cross-section is ...
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Symmetries and conservation laws for a falling cat
For Hamiltonian systems, symmetries and conservation laws are defined and related to each other by Noether's theorem. Symmetry means the invariance of the Hamiltonian for a transformation group, and ...
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String conservation with springs
I was trying to solve this Problem
that asked to find the period of small oscillations for this system.
To do so I used the fact that for a massless pulley with strings around it, the sum of the ...
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2
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Pressure of rubber band on cylinder taking friction into account
Suppose I have stretched a rubber band around a cylinder of radius $R$ such that the rubber band is under tension $T$. My understanding is that in the ideal situation, with no friction, the band ...
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