Question

Which of the following will change the time period as they are taken to the moon?
(a) A simple pendulum
(b) A physical pendulum
(c) A torsional pendulum
(d) A spring mass-system.

Answer 1

Answer ⇒ Option (a). and Option (b).

Both will change there Time Period when they are taken to the moon.

Explanation ⇒ Time Period of the Simple Pendulum is given by the Relation,

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

It depends upon g, and g changes on the moon. Thus, Time period of simple Pendulum will vary.

For a physical pendulum,

T = $2\pi\sqrt\frac{I}{mgh}$

It also depends upon g, and g changes on the moon. Thus, Time period of Physical Pendulum will also vary.

But, Time period Torsional Pendulum and the spring mass system does not depends upon the acceleration due to gravity and thus they will not vary on other planets.

Hope it helps.

Answer 2

Option (a). and Option (b).

Both will change there Time Period when they are taken to the moon.