(Solved): In the belt brake system shown in the figure, the winding angle = and the rotor d ...

In the belt brake system shown in the figure, the winding angle ? = ????????????° and the rotor diameter r = 60 mm. Calculate the braking torque by taking the friction coefficient 0.25. If the drum is 1500 If it rotates with rpm, how long is the braking time? (the moment of inertia of the rotor J = 2 kg-m2 )