Question

A pendulum swings through an angle of 30º and describes an arc 8.8 cm in length. Find the length of the pendulum.

Answer 1

Here, q = 30º, l = arc = 8.8 cm

`\therefore l=\frac{\theta }{360}\times 2\pi r`

`8.8=\frac{30}{360}\times 2\times \frac{22}{7}\times r`

`r=\frac{8.8\times 6\times 7}{22}=16.8 `