All Questions
Tagged with classical-mechanics reference-frames
204
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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 ...
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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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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....
CommunityBot
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Properties of the Center of Mass
My students are currently going through the rigid rotor and hydrogen atom unit in their quantum physical chemistry course and I found myself at a loss on how to justify what seems a natural way to ...
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The square of the center of mass [closed]
In the book Classical Mechanics by Goldstein, there is an exercise related to the square of the position of the center of mass of a free particle. I must prove that
$$M^2R^2 = M\sum_i m_ir_i^2 - \...
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Does relative motion allow for speeds $>c$?
If motion is relative, (so if X was stationary and Y was moving at v m/s, we could think of this as Y being stationary and X moving at -v m/s), could we not create a scenario in which a stationary ...
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Derivative of angular velocity in a rotating frame
Taylor Relies on these relations
$v = \omega \times r$
$\frac{d}{dt}Q = \omega \times Q$
To show that
$a = a' + 2 \omega \times v' + \omega \times \omega \times r' + \alpha \times r' ...
CommunityBot
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Decomposing Lagrangian into CM and relative parts with presence of uniform gravitational field
Most problems concerning two-body motion (using Lagrangian methods) often only consider the motion of two particles subject to no external forces. However, the Lagrangian should be decomposable into ...
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Energy in different coordinates in central force motion
With reference to central force, we see that K.E has 2 terms in 2D cartesian cordinate but just 1 term in polar coordinates and potential energy has 1 term in cartesian but 2 terms in polar.
Basically ...
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Doppler shift phenomenon for non-inertia frames
The Doppler shift phenomenon is well understood when the source and observer are in relative constant motion. However, I'm curious to know how the Doppler shift phenomenon is modified when they (i.e., ...
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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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Find COM velocity with respect to laboratory reference frame [closed]
I'm trying to solve the following homework question.
Suppose that in the laboratory frame of reference we have $2$ particles. Particle "$a$" is at rest with total energy $E_a$, while ...
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Why isn't there such a thing as "internal momentum"?
The three most well-known conserved quantities in classical physics are energy, momentum, and angular momentum.
Suppose we have a system with no external forces acting on it. We can talk about the ...
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What is the velocity of centre of mass in centre of mass frame?
Velocity of centre of mass in centre of mass frame is considered zero. But how are the two contradictory statements written in the book?
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How do physicists determine where to place the world or inertial frame when describing the equation of motion of an object?
For example, I have a pendulum as shown in the diagram above. I would like to write down its equation of motion. To do this, I must define a world frame (or inertial frame, or origin).
But this is ...
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