A person measures the time period of a simple pendulum inside a stationary lift and finds it to be T. If the lift starts accelerating upwards with an acceleration g/3, the time period of the pendulum will be

Question

A person measures the time period of a simple pendulum inside a stationary lift and finds it to be T. If the lift starts accelerating upwards with an acceleration g/3, the time period of the pendulum will be (A)  √3T  (B)  T/√3  (C)  (√3T/2)  (D) T/3

Tardigrade Admin · Accepted Answer

Time period of the simple pendulum in the lift

T = 2 π \frac{l}{g a}

Time period when lift starts accelerating upwards with acceleration

g /3

T = 2 π \frac{l}{g + \frac{g}{3}}

T = 2 π \times 3 \frac{l}{4 g}

or

T = 2 p \frac{l}{g} \times \frac{3}{2}

or

T = \frac{3}{2} T

Q. A person measures the time period of a simple pendulum inside a stationary lift and finds it to be $T$ . If the lift starts accelerating upwards with an acceleration $g /3$ , the time period of the pendulum will be

$3 T$

$T / 3$

$\frac{3 T}{2}$

$T /3$

Time period of the simple pendulum in the lift
$T = 2 π \frac{l}{g a}$
Time period when lift starts accelerating upwards with acceleration $g /3$
$T = 2 π \frac{l}{g + \frac{g}{3}}$
$T = 2 π \times 3 \frac{l}{4 g}$
or $T = 2 p \frac{l}{g} \times \frac{3}{2}$
or $T = \frac{3}{2} T$

Q. A person measures the time period of a simple pendulum inside a stationary lift and finds it to be T. If the lift starts accelerating upwards with an acceleration g/3, the time period of the pendulum will be

3​T

T/3​

23​T​

T/3