Question

Find the length of the arc which subtends ${120}^o$ angle at centre of circle whose radius is 21 cm.

• A. 11 cm
• B. 22 cm
• C. 44 cm
• D. 88 cm

Answer 1

The correct option is C 44 cm

Length of arc = $\frac{Angle}{{360}^o}$$\times$2$\pi$r
= $\frac{{120}^o}{{360}^o}$$\times$2$\times$$\frac{22}{7}$$\times$21
= $\frac{1}{3}$$\times$2$\times$$\frac{22}{7}$$\times$21
= 44 cm