Question

Choose the correct option which doubles the time period of pendulum. Pendulum is oscillating with small amplitude having mass m and length of string $\ell$.

• A. Doubling the mass m of the bob
• B. Doubling the initial force used to set the pendulum in motion
• C. Doubling the amplitude of the pendulums swing
• D. Quadrupling the mass m of the bob
• E. Quadrupling the length $\ell$ of the pendulum

Answer 1

Answer: (E)

Quadrupling the length $\ell$ of the pendulum

The time period of a simple pendulum is given by

$T=2\pi \sqrt{\frac{L}{g}}$

Thus quadrupling the length of pendulum $L$ doubles the time period of the pendulum.