Question

The bob of a pendulum is made of a hollow brass sphere. What happens to the time period of the pendulum, if the bob is filled with water completely? Why?

Answer 1

Time period is given by, $T=2\pi\sqrt{\frac{l}{g}}$, where l is length of simple pendulum and g is acceleration due to gravity.

The time period of the simple pendulum is same , when the bob is hollow or completely filled with water.

as water flows out from the bob , the centre of gravity of the bob lowers. due to this length of simple pendulum increases. hence time period also increases.


when the bob becomes empty, centre of gravity of bob shifts upwards and then length of simple pendulum decreases , hence time period also decreases.

Answer 2

HEYA MATE HERE U GO.

❤. When the hollow brass sphere is completely filled water , then there is no change in the effective length of the pendulum .

❤. So there is no change in its time period.