Two block A and B are connected to a spring (force constant k = 480 N/m) and placed on a horizontal surface. Another block C is placed on B. The coefficient of friction between the floor and block A is `mu_1 = 0.5`, whereas there is no friction between B and the floor. Coefficient of friction between C and B is `mu_2 = 0.85`. Masses of the blocks are `M_A = 50 kg, M_B = 28` kg and `M_C = 2 kg`. The system is held at rest with spring compressed by `x_0 = 0.5 m`. After the system is released, find the maximum speed of block B during subsequent motion.

Answer

4 m/s