Let h be the height through which the coin is dropped. Then, according to the equation of motion, it is given as h=ut+21gt2⇒t= g2 h[∵u=0]⇒t∝g1 As the elevator is moving uniformly i.e. its velocity is constant, so the acceleration is zero. ∴ Relative acceleration of the lift when it is either moving upward or downward is given as, g′=g±a=g±0=g Hence, the time for the coin to reach the floor will remains same i.e. t1=t2.