Why Does Friction Act in the Same Direction as the Force on a Rotating Disc?

AI Thread Summary
Friction acts in the same direction as the applied force on a rotating disc because it opposes the motion of the surface beneath it. When a force is applied tangentially to the disc, it causes the disc to rotate, pushing against the surface in the opposite direction. This results in friction acting to prevent slipping, thereby aiding rotation rather than hindering it. The relationship between the direction of the applied force and friction is crucial for understanding the dynamics of the system. Ultimately, friction facilitates the disc's rotation while resisting translational movement.
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Homework Statement



"Friction hinders translation but aids rotation"
If a uniform disc is placed on a surface and a force is applied tangential to it, why is the direction of friction same as that of the force. This would surely hinder rotation and aid translation, right?

Homework Equations



This is not a problem.

The Attempt at a Solution


Out of ideas. Thought a lot about it.
 
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I believe what they are trying to say is when the disk spins, it is pushing the surface in the opposite direction of which it is moving. Think about it: when you push against the ground, you move in the opposite direction of your push. Therefore, the friction is in the opposite direction of which it is spinning.
 

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