Questions tagged [rotational-dynamics]
A tag for questions about the mechanical interactions of rotating objects, including torque and angular momentum.
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How does the moment of inertia work in this physics question? (Vibrations and Waves by George C. King) [closed]
Not sure if this is just me having a moment where I'm missing something totally obvious, but I'm going over some old undergraduate physics work to reinforce my knowledge, and I've encountered a step ...
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Calculating the amount of torque applied to to stop a rod rotating at some angular velocity
Consider a Rod AB, having length $l$ with non uniform mass density $\lambda (x) $ a function of length from the end A, is rotating at an angular velocity $\omega$ with fixed end A and free end B. ...
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Implicit definition of internal forces through choice of dynamical description of a rigid two mass pendulum
The central mass theorem states that the center of mass of a N-body system moves as if all external forces acting on the bodies of the system acted directly on the center of mass, it is a generic ...
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Rolling ball on a surface with friction
For a point particle moving on a surface under the infuluence of gravity, the equation of motion is very easy to write down - the force on the particle is simply the projection of its weight $mg\...
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Dragging a homoegenus cylinder without slipping [closed]
We drag a homogeneous solid cylinder of mass $m$ along a horizontal surface, which rolls without slipping. What is the acceleration of the center of gravity? On the sketch, draw the directions and ...
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Coriolis force on a particle moving on sphere
Consider a particle moving on a rotating disc, as shown below. The direction of the Coriolis force acting on the particle can be found using the cross-product of the angular velocity vector and the ...
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Do off-centre forces create additional energy?
When a force is applied to a rigid body at its centre of mass, it accelerates. Over time, that acceleration becomes velocity, which gives the body a certain amount of kinetic energy.
However, if that ...
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Acceleration due to a spinning sphere [closed]
If a person is on a spinning sphere and he jumps will his acceleration downward equal to $g$? And will there be any difference if another person at rest is observing?
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Motion of bowling ball
I'd like to model the motion of an asymmetric bowling ball thrown on a bowling lane. I know there's forward momentum and angular momentum that moment the ball is released, and there's of course ...
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Avoiding secondary flow in rotating fluid
I am required to create an annular flume for an experiment. The flume is to be filled with water, and a paddle is to be dipped into the water and rotated along the flume at some fixed angular velocity ...
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Relationship between varying radius of ball and its affect on time taken for ball to come to rest in a spherical hemisphere while moving in a circle
I am a high school student trying to figure out the theoretical relationship between the radius of a ball that is launched into a bowl (moves in a circular path in the bowl) and the time taken for it ...
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Doubt regarding angular momentum conservation
in the above question I have doubt regarding validity of angular momentum conservation.
The question is solved by conserving angular momentum about axis of larger disc as follows;
$$0 = -\frac{1}{2} M(...
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Why isnt the contact force between the rack and wheel 200N?
I was looking at this YouTube video 'Example 1' (from 4:17 timepoint) and wondering why the contact force F between the rack and wheel isn't also 200N? Isn't this constant force of 200N being ...
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Rotation of a mass attached to a spring
Consider a case where a ball or object of mass $m$ is attached to a spring that is hinged at one point. If the ball is given a velocity perpendicular to the spring, it does spiral motion due to ...
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Does moving the idler in a wheel and disk CVT conserve energy or momentum? [closed]
Consider the wheel and disk CVTs (continuous variable transmissions) below. Configuration A comprises a CVT disk coupled to the "system under control" 's', whereby a control wheel 'cw' ...
