Question

Please help with this AP Physics 1 problem

Answer 1

Answer:

i) kinetic friction; ii) The friction force always acts in the opposite direction to the movement of the surface where friction exists.

Explanation:

Part i )

At that time the type of friction that exists is kinetic, as there is movement by the wheel. At the moment when the wheel remains in rest over the inclined plane, the friction force which would be used will be the static force.

Part ii)

The friction force always acts in the opposite direction to the movement of the surface where friction exists. It is not opposed to the sense of movement. In order for the wheel to rise on the inclined plane, it must turn to the right, that is to say in the clockwise direction, therefore the friction force must go in the opposite direction to the rotation of the wheel, that is to say, go in the opposite direction to the movement of the surface under friction effect, that is why it points in the same direction of displacement of the wheel.