Question

A loop of radius 2 m weights 100 kg. It rolls along a horizontal floor so that its centre of mass has a speed of 20 cm/s. How much work is done to stop it?

Answer 1

R = 2 m, M = 100 kg

v = 20 cm/s = 0.2 m/s

Total energy of the loop

Work required to stop the hoop = total energy of the hoop

= 100 (0.2)² = 4