A pendulum is made to hang from the ceiling of an elevator. It has period of T sec [for small angles). The elevator is made to accelerate upwards with 10 m / s 2. The period of the pendulum now will be (Take g =10 m / s 2 )

Question

A pendulum is made to hang from the ceiling of an elevator. It has period of T sec [for small angles). The elevator is made to accelerate upwards with 10 m / s 2. The period of the pendulum now will be (Take g =10 m / s 2 ) (A)  T√2  (B) infinite (C)  T/√2  (D) zero

Tardigrade Admin · Accepted Answer

When the elevator is at rest, its time period is given by

T = 2 π \frac{I}{g} = 2 π \frac{I}{10}

When the elevator accelerates upwards,
its time period becomes.

T = 2 π \frac{I}{g + a} = 2 π \frac{I}{10 + 10}

= 2 π \frac{I}{20} = 2 π \frac{I}{10} \times \frac{1}{2}

= \frac{T}{2}

Q. A pendulum is made to hang from the ceiling of an elevator. It has period of $T$ sec [for small angles). The elevator is made to accelerate upwards with $10 m / s^{2}$ . The period of the pendulum now will be (Take $g = 10 m / s^{2}$ )

$T 2$

infinite

$T / 2$

zero

When the elevator is at rest, its time period is given by
$T = 2 π \frac{I}{g} = 2 π \frac{I}{10}$
When the elevator accelerates upwards,
its time period becomes.
$T = 2 π \frac{I}{g + a} = 2 π \frac{I}{10 + 10}$
$= 2 π \frac{I}{20} = 2 π \frac{I}{10} \times \frac{1}{2}$
$= \frac{T}{2}$

Q. A pendulum is made to hang from the ceiling of an elevator. It has period of T sec [for small angles). The elevator is made to accelerate upwards with 10m/s2. The period of the pendulum now will be (Take g=10m/s2 )

T2​