Question

In a circle of radius 21 cm an arc subtends an angle of ${56}^{\circ }$ at the centre of the circle. The length of the arc is

• A. $20.53$ cm
• B. $17.53$ cm
• C. $15.53$ cm
• D. $16.53$ cm

Answer 1

The correct option is A $20.53$ cm

$\theta ={56}^{\circ },r=21cm$
Length. of $AB=\frac{{56}^{\circ }}{{360}^{\circ }}\times 2\times \frac{22}{7}\times 21$
$=\frac{616}{30}=20.53cm$