All Questions
Tagged with classical-mechanics reference-frames
30
questions with no upvoted or accepted answers
3
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1
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What frame of refernce to select in statistical mechanics?
Suppose we have a solid particle suspended inside a fluid such as an ideal gas, as shown in the following picture:
Our system is the solid particle and the environment is the gas (which acts as a ...
- 1,648
3
votes
1
answer
137
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These components of the angular velocity are given in what reference frame?
When we have a rigid body, the rigidity constraint allows us to write the trajectory $\mathbf{r}_i$ of the $i$-th particle as
$$\mathbf{r}_i(t) = R(t)\mathbf{b}_i + \mathbf{w}(t),$$
where we are ...
- 36.4k
3
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130
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Gauge formalism in rigid body mechanics
When doing calculations in rigid body mechanics, it is necessary to choose an origin to calculate torques and angular momenta. However, the underlying dynamics does not depend upon the choice of that ...
user17116
2
votes
1
answer
673
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Possible error in Marion and Thornton's Classical Dynamics of Particles and Systems
I was going over my notes on classical mechanics and just started to review rotation matrices which is the first topic the book starts with. On page 3
The rotation matrix associated with 1.2a and 1....
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0
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36
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How do 4-vectors change under an "accelerated" Lorentz transformation?
I assume that an observer moving with velocity $\mathbf{v} = v\mathbf{n} = \mathbf{v}(t)$ (with respect to another observer) has coordinates
where $x^{\mu}$ are the coordinates for the observer who ...
- 391
1
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How to define differentiation of a time-dependent vectors with respect to a specific reference frame in a coordinate-free manner?
It is usual in classical mechanics to introduce the derivative of a time-dependent vector with respect to a reference frame. This is accomplished through the use of a basis that is fixed with respect ...
- 245
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Why does my toothbrush topple on rebound?
I noticed this with my toothbrush the other day, but I feel that I have witnessed it happening before.
I accidentally knocked my hand into my toothbrush (electric toothbrush, can stand upright on its ...
- 163
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0
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136
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Assumptions in Galilean and Relativistic Frame Transformation
While deriving the frame transformation equations, either the Galilean Transformation or Lorentz transformation. I have seen almost all authors mentioning/assuming that if an inertial frame $\textbf{S}...
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1
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Doubt on the difference between a rotational coordinate system and spherical coordinate system and the calculation of the Christoffel sysmbols
I know basic differential geometry for general Relativity and classical mechanics. But an interesting fact was revealed in my calculations, namely, that I discovered that I didn't realize the ...
- 3,085
1
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Reference Frame conceptual confusion
I am getting confused as to why a ball still feels gravity when inside a moving car. The point of a reference frame is to reinterpret all the forces acting on a particle in one frame only. Hence all ...
1
vote
0
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401
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Angular velocities in moving reference frames
Please refer the image below for a clear idea of my question.
So, the instructor has written the angular velocity of the wheel, w.r.t. ground and the unit vectors he used are the ones for the frame B....
- 346
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306
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Rigid Rotor, Heisenberg Picture
I'm running into a problem where a rigid rotor in the the (non-inertial) principle axis frame of reference seems to violate Ehrenfest's theorem by a minus sign.
Consider a rigid rotor with ...
- 321
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59
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Justifying that the gold nucleus is at rest in a Rutherford experiment
This is an example on the Rutherford Experiment from Young and Freedman's University Physics.
In the last paragraph of the solution the book states that it is valid to assume that the gold nucleus ...
0
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0
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19
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2d elastic scattering with an impact parameter
Hello guys I have homework that has tasked me with connecting the effect of the scattering parameter to the energy transfer in a 2d elastic collision of two arbitrary spheres with one of them standing ...
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Reading on weighing scales at the equator of a moon in a tidally locked two-body system
I'm trying a made-up extension of this problem. Consider the planet Mars and its moon Deimos, which can be approximated as meeting the following simplifying conditions:
Both objects are perfect ...
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