A uniform circular disk with radius 0.2m and moment of inertia 0.3kgm2 is mounted on the fix horizontal axle through its center. the axle exerts a frictional torque on the disk. a block with the mass 5kg hangs from the rope that is wrapped around the rim of the disk . the block fall down 16m in the time 4s when released from rest.
Find the angular acceleration of the disk and find the magnitude and direction of the frictional torque.