Blocks A and B are released from rest when the spring is unstretched. Block A has a mass m...

Blocks A and B are released from rest when the spring is unstretched. Block A has a mass mA = 2 kg, and the linear spring has stiffness k = 7 N/m. If all sources of friction are negligible, determine the mass of block B such that B has a speed υB = 1.5 m after moving 1.2 m downward, assuming that A never leaves the horizontal surface shown and the cord connecting A and B is inextensible.

Figure P4.56