Question

The bob of a simple pendulum of length $1m$ has mass $100g$ and a speed of $1.4m/s$ at the lowest point in its path. Find the tension in the string at this instant.

Answer 1

Mass, $m=100$ $g=0.1$ $kg$

Length, $l=1$ $m$

at its lowest point, the only force acting on it is tension only.

$\therefore T=\frac{m{v}^2}{l}$

$⟹T=\frac{0.1\times 1.4\times 1.4}{1}$

$⟹T=0.196$ $N$