Questions tagged [rotational-kinematics]
A tag for questions about rotational motion, including angular velocity and angular acceleration.
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Velocity of an stationary object when viewed from rotating disk
Suppose I am sitting at the centre of a rotating disk, having an angular speed of 3 radian per second and I observe a tree 4 meters away from me. The tree will have a velocity of 12 meters per second ...
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How do I approximate an angular acceleration vector from a history of orientations?
A rigid body is simulated to move in six degrees of freedom. At every past timestep, I know its displacement vectors $x^{GLOB}$ in the global coordinate frame, as well as 3x3 matrices $R$ that ...
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Does always angular momentum and angular velocity have the same direction?
I was studying how angular momentum is cancelled when it is transferred directly into the origin of the axis of rotation and during the lecture the professor did something and I was pretty confused.
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Relationship between angular and translational velocity on inclined surface
I have been researching about rolling motion and I was calculating a way to predict the translational velocity of the object at the bottom of the incline. I know that the kinetic energy of a cylinder ...
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Will a cylinder/sphere roll on a rope if half of it is surrounded by rope and one end of the rope being pulled?
Rolling a cylinder using a rope having one end fixed and another end mobile
Will the cylinder/sphere roll as per the conditions mentioned in the above question(link)? Are there any additional ...
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Help with derivation of Kinetic Energy of N point masses
There are $N$ point masses as shown in image each with mass $m_i$ and velocity $v_i$.
We need to find the Kinetic Energy of the system. Here is the proof attached I have some doubt in it.
The doubt ...
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How to find angular velocity vector of a three dimensional rigid body given velocity of three non-collinear points on the same?
The position of a three-dimensional rigid body is completely defined by specifying position vectors of three non-collinear points on the body.
Similarly, one can define the motion of the rigid body by ...
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Is there a source that gives a comprehensive framework for tranformations between relatively rotating reference frames?
This is an example of the kind of discussion I am interested in.
Imagine we have a large rotating turntable, kind of like a merry-go-round, but made of some transparent material. On its surface, as ...
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How can I calculate the inertia tensor of a hollow object defined by a triangle mesh?
I want to calculate the mass, center of mass, and inertia tensor of player created objects. Some of the objects will be hollow instead of solid. I am creating a closed triangle mesh for their object. ...
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Strange pattern on fast spinning CD
In the following youtube video and timestamp:
http://www.youtube.com/watch?v=zs7x1Hu29Wc&t=6m51s
one can see a cd spinning very quickly, in slow motion, just before it breaks. I'm not sure I ...
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Particle in Cyclone - height of pipe that will keep the particle pressed against the inside wall
I'm trying to determine the required radius, $R$, and length of a hollow cylinder, $L$, to keep a particle that enters tangentially with an initial velocity $V_{t,i}$ at the top of the cylinder "...
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Calculate a rotational speed for an object spinning in 3 axes
I've got an object spinning in 3 axes and I'm tracking it with a motion capture system. For each timepoint, depending on how I export the data, I either get 4 columns of data for the quaternion ...
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Difference between nutation and polar motion
If you add a mass to your spinning globe or just change the mass distribution does it increase nutation or polar motion? And How do I calculate nutation? For this I take earth as an example. from what ...
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Why is a mechanical advantage less than 1 required for class 3 levers?
From what I understand, mechanical advantage is equal to the ratio of force produced to force applied, which is equal to the ratio of effort to load and effort arm length to load arm length
Therefore,...
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Angular velocity of a particle moving in 3D
I have a particle trajectory where particle position is available at discrete time steps with respect of (0,0,0) in 3D. Time step is 0.05 sec. For reference, positions are shown in following image.
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