All Questions
Tagged with classical-mechanics reference-frames
204
questions
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Do released objects take the direction and speed of their parent frame's velocity, or just the parent frame's speed component?
Context: I'm working on a space game. I noticed that an unpowered object fired from a strafing spaceship appeared, as the released object moved, to curve in the direction the ship was strafing. This ...
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votes
1
answer
35
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Center of Mass calculation in configuration of $3$ pennies inscribing equilateral triangle [closed]
I'm working on a problem that is asking me to solve the moment of inertia about the center of mass of a $3$ penny system where the edge of each penny is touching the edge of the others and the ...
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5
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158
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Torque Intuition [duplicate]
We are all taught that the torque $\boldsymbol{\tau}$ is given by $\boldsymbol{\tau} = \mathbf{r}\times\mathbf{F}$ so that torque increases with the lever arm length. What is the physical intuition ...
- 223
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2
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Center of mass in hydrogen atom
I have few questions regarding quantum treatment of the hydrogen atom problem.
Why does one changes coordinate from position vector of electron and nucleus to COM coordinates and relative position ...
1
vote
1
answer
91
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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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In terms of which zero should i calculate the potential energy in the Lagrangian formalism?
What I understand is that we have two kinds of coordinates when working with the Lagrangian formalism with different zeros (which may happen to coincide) to measure from, those are the Cartesian ...
- 959
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1
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94
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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
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3
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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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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, ...
- 675
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Why is a reference frame moving with constant velocity with respect to an inertial frame also inertial?
We define an inertial frame, as a frame of reference where:
Newton's 1st law holds.
It is then stated that a reference frame moving with constant velocity with respect to an inertial frame is also ...
- 1,648
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241
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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 ...
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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
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2
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61
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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:
$$ j=-3v_r \omega^2 e_r ...
- 2,035
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2
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115
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When to apply $I_c \underline{\omega} = \underline{M_c}$?
I was solving an exercise the other day, about a rolling cylinder on an inclined plane. Initially the cylinder slides, but then it begins to roll and the problem wanted to know the velocity of the ...
- 402
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Problem 6.3 from David Morin (classical mechanics) [closed]
I get the lagrangian for the system as
$$
\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 ...
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