Questions tagged [classical-mechanics]
Classical mechanics discusses the behaviour of macroscopic bodies under the influence of forces (without necessarily specifying the origin of these forces). If it's possible, USE MORE SPECIFIC TAGS like [newtonian-mechanics], [lagrangian-formalism], and [hamiltonian-formalism].
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Designing a thought experiment on Noether's Theorem [closed]
By Noether's theorem, in classical physics, conservation of total momentum of a system is result of invariance of physical evolution by translation.
So logic says "if" there exists closed ...
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Is my solution for Morin 3.7 Correct [closed]
I already posted this question on PF and wanted some opinions from stack exchange. Essentially I want to know if my approach is correct.
Reference: https://www.physicsforums.com/threads/morin-3-7-...
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Non-inertial frames in quantum mechanics
In classical physics, non-inertial frames necessitate adjustments to Newton's laws due to acceleration and rotation, yet in general relativity, Einstein successfully incorporates such frames. Why does ...
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In equation (3) from lecture 7 in Leonard Susskind’s ‘Classical Mechanics’, should the derivatives be partial?
Here are the equations. ($V$ represents a potential function and $p$ represents momentum.)
$$V(q_1,q_2) = V(aq_1 - bq_2)$$
$$\dot{p}_1 = -aV'(aq_1 - bq_2)$$
$$\dot{p}_2 = +bV'(aq_1 - bq_2)$$
Should ...
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Invertibility between generalized and actual coordinates
Chapter $1$, page $13$ of Classical Mechanics by Goldstein ($2^{nd}$ edition), he states the following after defining a transformation equation:
"It is always assumed that one can transform back ...
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Meaning of $d\mathcal{L}=-H$ in analytical mechanics?
In Lagrangian mechanics the momentum is defined as:
$$p=\frac{\partial \mathcal{L}}{\partial \dot q}$$
Also we can define it as:
$$p=\frac{\partial S}{\partial q}$$
where $S$ is Hamilton's principal ...
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Why aren't all objects and their images same in size?
Suppose there is an object in front of a convex lens and we know that the light rays from each point on the surface of object will converge at a different point and form an image. So that means that ...
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Prerequisites for studying Lev Landau Mechanics vol. 1 [closed]
Lev Landau Mechanics vol. 1 dives directly into Lagrangians and Hamiltonians. What do you think are the prerequisites in order to study and grasp it?
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Relating Brachistochrone problem to Fermat's principle of least time [closed]
When I came across the Brachistochrone problem, my teacher said we could relate it to Fermat's principle of least time.
So, we could make many glass slabs of high $\mathrm dx$, and every slab has a ...
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Equilibrium over a parabola [closed]
Find the angle respect vertical of the equilibrium position of a rod of length L and M kg. with an extremun on a vertical parabola and passing by the focus of the parabola
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Particle is attracted by a force to a fixed point varying inversely as nth power of distance [closed]
particle is attracted A particle is attracted by a force to a fixed point varying inversely as nth power of distance . ... See the image
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Why the interaction between system and thermal bath does not affect the energy levels of the system?
When we write down the full Hamiltonian of a system in contact with a thermal bath, it is as follows:
$$H_{\text{total}} = H_{\text{system}} + H_{\text{system+bath}} + H_{\text{bath}}.$$
As our focus ...
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Work performed by hydrostatic pressure
One should be able to show mathematically that the hydrostatic work done by an environment on an object undergoing a volume change $\Delta v$ should be $p \Delta v$, where $p$ is the (constant) ...
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How to compute the vector field from a potential in the complex plane?
I am watching this Youtube video and I have the following dumb question around 1:18:00: How do you draw the vector field for a given potential in the complex plane? He gives the potential $V(x) = x^4-...
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Does Hamilton's principle allow a path to have both a process of time forward evolution and a process of time backward evolution?
This is from Analytical Mechanics by Louis Hand et al. The proof is about Maupertuis' principle. The author seems to say that Hamilton's principle allow a path to have both a process of time forward ...
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