JEE Main · 2023 · 01 Feb 2023 · Shift 2 · Elasticity & SHM

For a simple pendulum the time period is $T=2\pi \sqrt{\frac{\ell }{g}}$, so squaring gives $T^2=\frac{4{\pi }^2}{g}\ell$. Thus $T^2$ is directly proportional to the length, and the graph relating the length and $T^2$ is a straight line of positive slope passing through the origin. The correct graph is the one showing a straight line rising from the origin.