A hollow pipe of mass 'm' and radius 'r' supported by a massless string tightly wind over it. A constant force is applied through the string such that the pipe remains at its position.
Find the length of the string unwound at time, . (Given, acceleration due to gravity = g)

for translator equilibrium

Taking torque a bout the centre of mass -
Angular displacement of the pipe at
Length of the string unwound from the pipe be ' L '