Identify the incorrect statement(s) from the following :

(I) The time period of oscillations depends on the extent of swing on either side.

(II) The time period of oscillations is directly proportional to the square root of acceleration due to gravity.

(III) The time period of oscillations is inversely proportional to the square root of its effective length.

(IV) The time period of oscillations does not depend on the mass or material of the suspended body.

1. (II) and (III)
2. Only (II)
3. Only (IV)
4. (I), (II) and (III)

(I), (II) and (III)

Reason — Time period of a simple pendulum is given by : $\text T = 2 \text π \sqrt{\dfrac{\text l}{\text g}}$

where

T = time period
l = effective length of pendulum
g = acceleration due to gravity.

From above relation it is clear that the time period of oscillations is inversely proportional to the square root of acceleration due to gravity and directly proportional to the square root of its effective length.

Hence, time period of a pendulum only depends upon its effective length and acceleration due to gravity.