Question

The period of a simple pendulum is doubled, when

• A. Its length is doubled
• B. The mass of the bob is doubled
• C. Its length is made four times
• D. The mass of the bob and the length of the pendulum are doubled

Answer 1

Answer: (C)

Its length is made four times

Answer 2

$T = 2\pi\sqrt{\frac{l}{g}}$ ⇒ $T \propto \sqrt{l}$