JEE Advanced Model Paper 17 with solutions for online practice

An atwood machine is setup in an elevator moving upward at 5m/s and slowing down at 2 m/s2 . The initial velocity of block B is 2 m/s upward and the acceleration of block A is 3 m/s2 downwards. Find the time (in sec.) at which block B will return to its initial position.Assume the string remains taut and the acceleration of the elevator does not change duringthe required time interval.