Two blocks are connected by a massless rope that passes over a pulley. M1= 2 kg and M2= 4 kg. The pulley is 12cm in diameter and has a mass of 2kg. As the pulley turns, friction at the axle exerts a torque of magnitude 0.5 Nm. if the blocks are released from rest, how long does it take the 4 kg block to reach the floor from a height of 1 m?