Questions tagged [rotational-kinematics]
A tag for questions about rotational motion, including angular velocity and angular acceleration.
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Euler angles and inertia tensor
Please note: What I'm looking for is $\alpha_0$ and $\beta_0$ in a form similar to Eq.(3) that will eventually give Eq.(1). Note that the inertia tensor is not a rotation matrix so I'm not trying to ...
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Kinematics of a rolling disk on a static disk (variation of the Euler disk)
I'm puzzled by the following problem. Consider a simple tilted disk $\mathcal{D}$ of radius 1 (in any unit) rolling without sliding on top of a static horizontal disk $\mathcal{S}$. The normal $\...
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If a body is lying on a frictionless surface, and we give it an impulse, will it start rotating about its center of mass?
If not, about what point will it rotate? If we want to know about what point an object will rotate in questions like these, how do we figure it out?
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Concept of polarization in microwave rotational spectroscopy
I am trying to understand the concept of polarization of molecules after they are excited by a microwave pulse. The context is:
The complexes are produced in a pulsed supersonic jet expansion of a ...
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Rotation of a sphere on two different axes
You have a small globe, which is mounted so that it can spin on the polar axis and can be spun about a horizontal axis (so that the south pole can be on top). Give the globe a quick spin about the ...
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If a weak light source is attached to a string, and someone swing this light source in circle. It seems that this light source is brighter. Yes or no
It may be truly a question of life and death.
You know those glow sticks.
As a sailor it is a good idea to carry one on our lifevest.
Falling into the sea, those glow stick make a light source that ...
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Why is the angular speed at the axis of rotation of a rotating disc equal to the angular speed at any other point on the disc?
I was just reviewing classical mechanics problems on Khan Academy and got the following question:
I knew that the angular speeds at points II, III, and IV must be equal, but I'm not sure how you'd ...
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Non-Euclidean geometry of rotating disc
Landau, in his Classical Theory of Fields Textbook remarks (while explaining GR) that a rotating disc viewed from an inertial frame of reference will no longer remain euclidean since the periphery ...
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Can some one explain to me why, when I include translational kinetic energy ($\frac{1}{2}mv^2$), I run into problems dealing with rotational motion?
Overall, the problems I know when to use it are when there is something like a rotating pulley disk which has a string wrung around it and a block at the end falling down. Another place I know when to ...
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Is there a reference frame in which the static friction from rolling does positive work?
I am worried this will be deleted as a duplicate question, so I will try to be extra clear what I am asking:
In some reference frames, static friction can do positive work. If you have a crate in the ...
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Could the source of dark energy be the universe rotating in a higher dimension?
As I understand it, the centrifugal force in a merry-go-round increases as we move further away from the center. Could the universe be spinning in a higher dimension (or even just spinning in a ...
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Do symmetric angular velocities lead to symmetric axis of rotation observed in a fixed frame?
It has been observed that some insects with relatively small stroke amplitudes (such as mosquitos) take advantage of a translating axis of rotation to generate lift where insects with larger stroke ...
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Thermal fluctuations in orientation of point particles
I am modeling group of point particles with 6 degrees of freedom each - 3 positional degrees of freedom and 3 orientational degrees of freedom. So, each particle has 3 position coordinates and a unit ...
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Model for rolling gears down a slope doesn't fit experiment
I have derived a model for what happens when one rolls a gear down a slope, and I have performed an experiment, however the experiment doesn't fit the model. Where did I go wrong?
The model
When a ...
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Motion of a catapulted point mass moving freely inside a spherical bucket
I am trying to study the motion of a point mass inside the bucket of a catapult.
The catapult is shooting downward (i.e. describing a rotation of 180° from the horizontal axis) and I would like to ...
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