All Questions
Tagged with rotational-kinematics friction
58
questions
6
votes
4
answers
4k
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Why do office chairs rotate when pushed/pulled out?
A common source of frustration when I'm at work is the fact that my rolling office chair's wheels rotate whenever I push it forward or backward from my desk, which can cause it to bump my computer ...
- 162
2
votes
3
answers
882
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Why does friction not accelerate a wheel?
It seems like a silly question because this defies common sense, but it appears that friction is supposed to accelerate a wheel (not attached to anything).
We can derive from Newton's laws that $\...
user113773
-1
votes
1
answer
252
views
Why should the friction between two disks be zero when there velocity is same? [duplicate]
In this video here, Walter Lewin mentions two discs of different radius $r_1$ and $r_2$, of the same density, where the first disk is initially rotating, while the second is at rest. In the videos ...
- 1,149
0
votes
1
answer
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The path of a disk/cylinder with translation and rotation [closed]
The conditions:
We have a regular disc of mass $\mathrm{M}$ and radius $\mathrm{R}$. It is placed on a horizontal plane with friction (which is constant throughout). It is then given an initial ...
- 151
0
votes
2
answers
686
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Friction during ball backspin and overspin
I already know sliding friction of ball on a flat table and rolling resistance of it.
How do I know coefficient of friction value when the ball has backspin with some angular velocity $\omega$? And ...
- 103
0
votes
1
answer
138
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Bearing spinning longer Horizontally
While performing a physics experiment, a fidget bearing was held horizontally, while spinning, and held vertically. The same torque was applied vertically, as well as horizontally on the bearings' ...
- 303
0
votes
2
answers
69
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In which case will the kinetic energy be more after reaching the bottom? [closed]
In which case will the kinetic energy be more after reaching the bottom? The shaded surface have friction and other are smooth.
I thought about these questions:
Does the answer depend on whether ...
- 215
5
votes
3
answers
385
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Why does it get harder with time, to rotate a screw with a screwdriver?
A couple of forces act on the machine screw and create the turning effect. But after sometime it gets harder. So, net torque is decreasing, but why is it decreasing? Frictional force comes into action,...
- 177
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votes
1
answer
198
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Why does no slipping occur when a particle is attached to a string, which is wound onto a circular disk, and the system is allowed to move?
In this question, the only way we can find the angular acceleration of the disc is by equating it to the linear acceleration of the particle divided by the radius. But this holds only if the string ...
- 254
0
votes
1
answer
876
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Why does a car moving at a roundabout move off in a tangent?
In the case where a car is inn circular motion at a roundabout, it moves off in a tangent when its speed surpasses the maximum speed. I understand why such tangential motion happens in the case of a ...
- 157
-1
votes
1
answer
50
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Rotational mechanics for ball
I got two questions
1)in pure rolling motion is angular acceleration and angular velocity same for a ball about its centre of mass and about its point of contact with ground?
2)if a ball is placed ...
0
votes
1
answer
221
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Barrel Rolling on concrete reverses its direction of motion
While reading my textbook I came across an activity which told :
Try rolling a barrel from concrete onto grass, what happens does the barrell reverses its direction of motion ? Is this because of ...
- 575
1
vote
2
answers
541
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Direction of frictional force on a particle on a plate in circular motion
If we have a particle on the surface of a round plate ,at a distance $r$ from the center, that is rotating with an angular acceleration $k$ , and this particle is in equilibrium with respect to the ...
- 95
0
votes
1
answer
1k
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Friction & relative motion
If there are two bodies that have zero relative velocity, does that mean friction will not exist between them, since friction opposes relative motion. In the figure below i have two wheels A&B, ...
- 119
3
votes
4
answers
8k
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In which direction does friction from the ground act on the wheel?
When a bicycle wheel is in motion, many forces are acting on it. The sum of the forces results in forward
motion. In which direction does friction from the ground act on the wheel?
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