An elevator without a ceiling is ascending up with an acceleration of 5 metres per second square.A boy on the elevator shoots a ball in vertical upward direction from a height of 2 metres above the floor of the elevator.At this instant the elevator is moving up with a velocity of 10 metres per second.The initial speed of the ball is 15 metres per second with respect to the elevator.What is the time in which the ball strikes the floor of the elevator ?

relative motion

let sign convention is +ve upwards

with respect to ceiling

acceleration of ball = -15 m/s^2

velocity of ball = 15 m/s

s=ut +1/2 at^2

-2 = 15t +1/2 (-15)t^2

solve

Even i got the same answer but the answer in the textbook is 2.13 seconds....plz help

Please answer these questions also for same situation (a) the maximum height reached by the ball as measured from the ground would be (b) displacement of ball with respect to ground during its flight would be (c)the maximum separation between the floor of elevator and the ball during its flight would be. Please answer these also