A small block of mass m is kept on a long plank of same mass. Ground is smooth and coefficient of friction between block and plank is 0.5. At t=0 initial velocity of 20 m/s is given to the system. At t=1sec plank is suddenly hinged such that it comes to the rest and at t=3sec again the hinge is removed. Neglect any frictional impulse.
1.Velocity of the block in time interval t=0 to t=1sec will be?
2.Displacement of the block in time interval t=0 to t=3sec?
3.Velocity of the plank after a long time is?