Physics - SHM Question with Solution | TestHub

The time period of a simple pendulum is
$$T=2\pi \sqrt{\frac{l}{g}}$$ Here, $l$ is the length of the pendulum. On squaring both sides $$\begin{array}{rl}& T^2=\frac{4{\pi }^{2}l}{g}\\ \Rightarrow & T^2\propto l\end{array}$$ So, the graph between time period $T$ and length $l$ of the pendulum is a parabola.