An arc of a circle subtends an angle of 30° on the circumference of a circle of radius 21cm. Find the length of the arc.
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Correct Answer: Option B
Explanation:
θ = 30 x 2(∠at center twice ∠at θ)
∴ θ = 60°
Length of arc = \(\frac{\theta}{360}\times 2\pi r\\
=\frac{60}{360}\times 2 \times \frac{22}{7}\times \frac{21}{1}\\
=22cm\)
θ = 30 x 2(∠at center twice ∠at θ)
∴ θ = 60°
Length of arc = \(\frac{\theta}{360}\times 2\pi r\\
=\frac{60}{360}\times 2 \times \frac{22}{7}\times \frac{21}{1}\\
=22cm\)