Question

The length of circumference of the circle whose arc of $16$ m length is making ${90}^o$ at ther centre of the circle ism.

Answer 1

We know,
$\text{Length of arc}=\frac{\theta }{{360}^o}\text{(circumference of circle)}$
Where, $\theta =\text{angle made by the arc at the center of the circle}$
putting, $\theta ={90}^o$ and
$\text{length of arc}=16$ m
$16=\frac{{90}^o}{{360}^o}\times \text{circumference}$
$\text{circumference}=16\times 4$
$\text{circumference}=64$ m.