Questions tagged [rotational-kinematics]
A tag for questions about rotational motion, including angular velocity and angular acceleration.
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Should the rotary vane damper torque be less than the load torque?
The rated torque of a rotary vane damper should be less than or more than the load torque?
In my opinion, if the rated torque is greater than the load torque of the damper, then I believe my ...
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Understanding the meaning of the directions of $\vec\omega$ and $\vec{L}$
I'm struggling with some basic intuition regarding the angular velocity $\vec\omega$ and angular momentum $\vec{L}$ vectors, for any arbitrary motion. Specifically, I'm trying to figure out what the ...
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Combined KE for an object rotating about a point other than COM
I know the KE equation for combined translational and rotational motion, which is $K=Mv^2/2+I\omega^2/2$, and here $v$ is the velocity of COM and $I$ is the moment of inertia about the COM. But what ...
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Understanding angular velocity $\omega$ as a vector
I would like to validate my understanding of angular velocity as a vector.
Suppose we have a particle $P$ moving around in $3D$ space in some arbitrary way. At any given point in time, we would like ...
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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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Can the same rough surface provide frictional force on opposite directions for translation and rotation of a sphere under a tangential external force?
I came across a question which says:
"A force $F$ acts tangentially at the highest point of a sphere of mass
m kept on a rough horizontal plane. If the rolls without slipping ,
find the ...
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Angular Velocity and Angular acceleration when the position vector is changing
I was watching a lecture about circular motion and how angular velocity and angular acceleration differ if origin changes.The teacher at 9:10 says that we cannot apply the formula $a=rα$ as position ...
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Relative angular acceleration
Let us consider a particle which is rotating in a circle of radius $R$ with a uniform angular velocity of $ω$. We are observing this particle from a frame rotating about the same axis with uniform ...
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Is the angular acceleration and the resultant acceleration the same thing? [closed]
Is the angular acceleration and the resultant acceleration of tangential and centripetal acceleration the same thing in non-uniform rotational motion? If not, what's the difference?
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What if an object is rotating near light speed? [duplicate]
lets say that we have a cube made of say 1kg, and using some means, managed to impart enough angular momentum to make it rotate at the speed of light or at least 99% of light speed. ignoring the fact ...
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Is the radius equal to length/radians? [closed]
Is the radius equal to the length/radians.
Since the circumference is 2 pi times r and radians of an entire circle is 2 pi r should be equal to lentgh/radians
I needed this proof to understand why we ...
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Rotating fluid shape with its own gravity
Hi almost every student knows the rotating bucket with a fluid problem as described here:
Fluid in a rotating cylinder
I wanted to do the same for a rotating fluid in free fall (like in the ISS) to ...
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Absolute Angular Velocity - How to use?
From my dynamics course, we were introduced to the so-called absolute angular velocity of a rigid body. Below is a short diagram:
The following equation for the velocity of point P on a rigid body is ...
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Confusion about conservation of energy with translational and rotational energy
This simulation has me confused about the conservation of energy. If both blocks have equivalent mass, and the velocity of the COM is equal, then they have translational kinetic energy equal to $K_{...
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Understanding how to measure angular momentum [closed]
In pure rotation, angular momentum is measured about the rotation axis. This angular momentum is measured with respect to that axis. Why do we consider it universal? It should change with respect to ...
