An arc of a circle subtends an angle π at the centre. If the leng
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An arc of a circle subtends an angle π at the centre. If the length of the arc is 22 cm, then what is the radius of the circle?
(Take π = 22/7)A. 5 cm
B. 7 cm
C. 9 cm
D. 11 cm
Please scroll down to see the correct answer and solution guide.
Right Answer is: B
SOLUTION
Angle subtended by full circle at center = 2π
Angle subtended by the given arc = π
∴ The arc is a semi-circle
Arc length of a semi-circle = π r = 22
⇒ 22/7 × r = 22
∴ r = 7 cm