Consider the system of two blocks shown in (Figure 1). There is no friction between block A and the tabletop. The mass of block B is 4.90 kg. The pulley rotates about a frictionless axle, and the light rope doesn't slip on the pulley surface. The pulley has radius 0.200 m and moment of inertia 1.40 kg⋅m2.
If the pulley is rotating with an angular speed of 8.00 rad/s after the block has descended 1.20 m , what is the mass of block A ?