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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Which of Kepler's laws would remain true if the force of gravity were proportional to the product of squares of each masses?
I was asked this question recently on which of the Kepler's Three law would remain if we changed the force of gravitation to be proportional to the product of squares of each masses instead of just ...
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Trying to derive relativistic dispersion formula
If we define conserved quantities of motion as constants arising from continuous symmetries of the system (Lagrangian), why does the following argument not give the correct result?
Let $\gamma: I \to ...
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On Landaus&Lifshitz's derivation of the lagrangian of a free particle [duplicate]
I'm reading the first pages of Landaus&Lifshitz's Mechanics tome. I'm looking for some clarification on the derivation of the Lagrange function for the mechanical system composed of a single free ...
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Subsequent motion (time evolution) of angled dipoles in electric field
Suppose we have a system of two dipoles, each with dipole moment $\mathbf{p}=2aq$ each aligned at angles $\theta$ and $-\theta$ with the horizontal. I’m thinking of an angle bracket shape, essentially....
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Definition of free fall in GR
I apologize if this question is very elementary. Somewhere I've found the following:
Freely falling observers (resp. photon) move on timelike (resp. null) geodesics.
Please note that by definition, ...
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Oscillating body and Doppler effect
Say we have a body attached to a spring, oscillating with some frequency $\nu$. This is one of the simplest problems studied in elementary Physics, and yet I've noticed we always study it positioning ...
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Why does classical physics not predict particles in the double-slit experiment to land in just two different locations?
I stopped being able to understand the double-slit experiment way before any of the interference and associated "quantum weirdness" came into play. I get that one needs to approach this ...
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How do I formulate a quantum version of Hamiltonian flow/symplectomorphisms in phase space to have a "geometric", quantum version of Noether's theorem
I'm currently exploring how Noether's theorem is formulated in the Hamiltonian formalism. I've found that canonical transformations which conserve volumes in phase space, these isometric deformations ...
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Are electrons in CRT classical objects?
Electrons in CRT seem to behave like classical objects with well-defined classical trajectories. But at the same time, it's elementary particles living in quantum world with weird quantum rules. How ...
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Position and displacement vector in Arc coordinate system
In Arc coordinate system the position of the particle is given by the length of the path(which is pre-determined and may also be curved) that it has travelled so how can we write it's position vector ...
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Wrinkling on a fluid foundation [closed]
I have this problem in fluid mechanics/elasticity and honestly don't know how to start.
A large elastic sheet of bending modulus A overlies a fluid of density $\rho$. Due to external compression, the ...
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Continuity Equation for Steady State Flow vs Incompressible flow
Good day guys,
I have been reading on the continuity equations on the slides of my fluid dynamics course.
I was introduced to the following definitions:
Steady state flow: $\forall f \in \text{Flow ...
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Angular velocity versor
I am going back through the definitions of good old Euclidean vectors and trajectories to see whether when i was younger i missed important concepts.
In my notes, and reference book, i found that for ...
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How did the boundary term vanish in deriving equation of motion from Lagrangian? [closed]
I was deriving the equation of motion from Lagrangian, by using the principle of least action. Usually, at this point in derivation,
$$\int dt \frac{\partial L}{\partial \dot{q}} \frac{\partial}{\...
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(Opinionish) Feynman Lectures Exercise: Use principle of virtual work to show the following about $n$ forces in static equilibrium
I would normally not want someone to provide a complete and well-stated solution to an exercise. In this case, that is exactly what I am seeking. The following exercise appears in Chapter 2 of the ...
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