An automobile moves on a road with a speed of 54 km h-1. The radius of its wheels is 0.45 m and the moment of inertia of the wheel about its axis of rotation is 3 kg m2. If the vehicle is brought to rest in 15 s, the magnitude of average torque transmitted by its brakes to the wheel is
As velocity of an automobile,
v=54km/h
=54 x 5/18
=15m/s
Angular velocity of a vehicle, v=ωor
=> ωo=v/R=15/0.45=100/3rad/s