All Questions
Tagged with classical-mechanics reference-frames
204
questions
8
votes
9
answers
2k
views
Different coordinate system as opposed to different reference frame
I'm having a hard time getting the difference between the two. In Euler's equations of rotating bodies for example, we have:
$$ \mathbf{\dot{L}}+\mathbf{\omega} \times \mathbf{L} = \mathbf{\Gamma},$$
...
- 2,829
2
votes
1
answer
378
views
Question regarding d'Alembert's principle
I am new to the subject of Classical Mechanics, I started with Principle of Least Action and now I am learning d'Alembert's Principle. Forgive my ignorance ,but I find it counterintuitive, according ...
CommunityBot
- 1
0
votes
1
answer
98
views
Trajectory of particle thrown from the center of rotating frame of reference
So we have a rotating platform with two frames o reference: the one which is static, $O:\{x,y,z\}$, and the one wich is rotating along the platform, $O':\{x',y',z'\}\ (z\equiv z')$. The platform is ...
- 296
4
votes
1
answer
392
views
Confusion about imposing constraint in the action
I'm totally confused by one thing. I know that I probably shouldn't be confused about that, but at the moment I don't quite know what fails in the following:
Suppose we have a particle of unit mass ...
- 207k
0
votes
0
answers
80
views
Substituting the conservation of angular momentum into the Binet formula results in contradiction [duplicate]
Background Information
The lagrangian of a particle in a central force field $V(r)$ is
$$
L=\frac12m(\dot r^2+r^2\dot\theta^2+r^2\sin^2\theta\dot\varphi^2)-V(r).
$$
The particle must move in a plane, ...
- 207k
0
votes
1
answer
241
views
Rotating reference frame - Taylor Problem 1.27 [closed]
I'm having trouble understanding how to think about Problem 1.27 in Taylor's Classical Mechanics. I want to be able to solve similar problems qualitatively when it comes to changing reference frame so ...
- 207k
3
votes
1
answer
47
views
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 ...
- 1,940
3
votes
2
answers
934
views
Rotating Rod As a conical pendulum
Consider A Rigid Rod hinged at its top point Whirled around in a circle (similar to a conical pendulum). It is given that the angular velocity (and thus the semi-vertical angle) is constant. I am ...
- 410
0
votes
2
answers
61
views
Inertial accelerations like the Coriolis effect are well known. Are there also 'inertial jerks' and what are some examples?
Inertial accelerations like the Coriolis effect are well known. Are there also 'inertial jerks' and what are some examples?
My guess would be that it would look something like:
$$ j=-3v_r \omega^2 e_r ...
- 41.1k
0
votes
2
answers
115
views
When to apply $I_c \underline{\omega} = \underline{M_c}$?
I was solving an exercise the other day, about a rolling cylinder on an inclined plane. Initially the cylinder slides, but then it begins to roll and the problem wanted to know the velocity of the ...
- 38.7k
0
votes
1
answer
149
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Problem 6.3 from David Morin (classical mechanics) [closed]
I get the lagrangian for the system as
$$
\begin{align}
\mathscr{L} = \frac{m}{2}(\dot{x}^2 + l^2\dot{\theta}^2 + 2l\dot{x}\dot{\theta}\cos \theta) + mgl\cos\theta
\end{align}
$$
Where $\theta$ is the ...
- 154
0
votes
2
answers
176
views
Lagrangian of inverted physical pendulum with oscillating base
An inverted physical pendulum is deviated by a small angle $\varphi$ and connected to an oscillating base with oscillation function $a(t)$. The pendulum's mass is $m$ and its center of mass is $l$ ...
- 21
4
votes
1
answer
61
views
Moving body is collided with a spring system.Why there is a difference in maximum compressed distance for different observers?
Suppose a body of mass m moving with velocity collides with a spring system.The event is being observed by two observers, one at rest and one moving with a velocity v opposite direction to that of the ...
- 1,070
0
votes
1
answer
65
views
Find the equation for the angle $\theta$ in which the particle leaves the semicircle. No Friction [closed]
I think I missed something in this mechanics problem.
We're given a polished (no friction) and homogeneous hemicircle which has mass $M$ and a particle of mass $m$ laying on the top of it.
There is ...
- 401
0
votes
1
answer
354
views
Banked curve problem in another frame of reference
How would you set up Newton's equation of motion for this problem (rolling without slipping in a circular path) using the frame of reference shown in the figure:
- 13.1k