Find the angle at which an arc of length 22 cm subtends at the centre of a circle of radius 15cm. [Take \(\pi = \frac{22}{7}\)]
A
70\(^o\)
B
84\(^o\)
C
96\(^o\)
D
156\(^o\)
Verified Correct Answer: B.
Step-by-Step Mathematical Solution
L = \(\frac{\theta}{360} \times 2 \pi r\)
22 = \(\frac{\theta}{360} \times 2 \times \frac{22}{7} \times 15\)
\(\theta = \frac{22 \times 360 \times 7}{2 \times 22 \times 15}\)
\(\theta\) = 84\(^o\)
Source: Myschool Past Questions Archive (Record #57272)