Question

In a circle of radius 21 cm, an arc subtends an angle of 60° at the centre. The length of the arc is ______.

Options

• 21 cm

• 22 cm

• 18.16 cm

• 23.5 cm

Answer 1

In a circle of radius 21 cm, an arc subtends an angle of 60° at the centre. The length of the arc is 22 cm.

Explanation:

We have r = 21 cm and θ =  60°

Length of arc `=theta/360^circxx2pi"r" = 60^circ/360^circxx2xx22/7xx21 = 22  "cm"`

Hence, the correct answer is option (b)