An athlete runs along a circular track of diameter 80 m . The distance travelled and the magnitude of displacement of the athlete when he covers $3 / 4$ th of the circle is (in m )

A particle is in uniform circular motion, related to one complete revolution of the particle, which among the statements is incorrect?

A car is moving in a circular horizontal track of radius $$10 \mathrm{~m}$$ with a constant speed of $$10 \mathrm{~ms}^{-1}$$. A bob is suspended from the roof of the car by a light wire of length $$1.0 \mathrm{~m}$$. The angle made by the wire with the vertical is (in rad)

A coin placed on a rotating turn table just slips if it is placed at a distance of $$4 \mathrm{~cm}$$ from the centre. If the angular velocity of the turn table is doubled it will just slip at a distance of