Question

Suppose a grandfather clock (a simple pendulum) runs fast. In order to make it run on time you should ... A. make the pendulum longer B. adjust the amplitude of the swing larger C. adjust the amplitude of the swing smaller OD. make the pendulum shorter

Answer 1

We know, the time period of simple pendulum is given by

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

Where, L is lenght of pendulum and

g is acceleration due to gravity = 9.81 m/s​​​​​​2

From above formula, time period of pendulum is only depend on the length of pendulum and it is directly proportional to square root of length.

It is given that grandfather clock (simple pendulum) runs fast i.e. time period is less.

(Since time period is time to complete a cycle)

Thus, in order to run it on time we have to increase its time period and for this we have increase the length of the pendulum.

Answer: A. To make pendulum longer