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How to determine the direction of friction acting on a purely rolling body like a cylinder when it is being accelerated? Is it in the directino of acceleration or not? I found out -
- Direction of friction aciting on a cylinder rolling down an incline is upward.
- Direction of friction acting on a cylinder roling up an incline is upward.
- Direction of firction acting on a cylinder being accelerated on a flat surface is in the direction of acceleration.
What is criteria that determines the direction of friction? Is it true friction acts so as to oppose relative motion? Further, I am not sure about statement 2. It might be wrong.