The radius of a circle is 21 cm. What will be the length (in cm) of an arc of the circle that subtends a 22.5° angle at the centre? [Use ]
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 8.25.
The radius of a circle (r) = 21 cm
The angle subtends( θ ) = 22.5°
l = (θ/360°)2πr
where, l = arc length, r = radius of a circle
l = (22.5/360°) × 2 × 22/7 × 21= 8.25 cm