Question

Static friction 6. A coin sits on a turntable as the table steadily rotates counterclockwise (CCW). What force or forces act in the plane of the turntable? Circle the correct choice on the figure at right and explain why the other two choices are incorrect in the space below. Static Centripetal force friction No forces in this plane

Answer 1

Force acting on the turntable is only the force of friction whose direction is represented below static friction A correet Therefore A will be the correct choice Since table is rotating steadily therefore its angular velocity is constant means there is no acceleration in tangential direction therefore no force acts in the tangential direction The force which moves the coin in the circular path is only the centripetal force which is provided by the friction and acts towards the centre of the turntable therefore option B is incorrect because the direction of static friction shown in diagram B is in tangential direction which must be in the direction towards centre and in case c there is no force which is not correct because centripetal force must act to provide circular motion