A coin is dropped in a lift. It takes time

Your Ultimate Guide to JEE & NEET Question Solutions

A coin is dropped in a lift. It takes time ${t_1}$ to reach the floor when lift is stationary. It takes time ${t_2}$ when lift is moving up with constant acceleration. Then

A

${t_1} > {t_2}$

B

${t_2} > {t_1}$

C

${t_1} = {t_2}$

D

${t_1} > > {t_2}$

A coin is dropped in a lift. It takes time ${t_1}$ to reach the floor when lift is stationary. It takes time ${t_2}$ when lift is moving up with constant acceleration. Then

For stationary lift ${t_1} = \sqrt {\frac{{2h}}{g}} $

and when the lift is moving up with constant acceleration

${t_2} = \sqrt {\frac{{2h}}{{g + a}}} $

$\therefore \;\;{t_1} > {t_2}$