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Question
Assertion (A): The length of the arc of a sector of a circle with radius $$14\ \text{cm}$$ and of central angle $$60^{\circ}$$ is $$\frac{88}{3}\ \text{cm}$$.
Reason (R): The length of the arc of a circle of radius $$r$$ cm and central angle $$\theta$$ is $$\left(\frac{2\pi r\theta}{360}\right)\ \text{cm}$$.
Options
Both Assertion (A) and Reason (R) are true and Reason (R) is a correct explanation of Assertion (A).
Both Assertion (A) and Reason (R) are true but Reason (R) is not a correct explanation of Assertion (А).
Assertion (A) is true and Reason (R) is false.
Assertion (A) is false and Reason (R) is true.
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Solution
Assertion (A) is false and Reason (R) is true.
Explanation:
Step 1 – Assertion: A is false. Using the stated arc-length formula:
\[\text{Arc length}=\frac{2\pi r\theta}{360}\]
\[=\frac{2\times\frac{22}{7}\times14\times60}{360}\ \text{cm}\]
\[=\frac{44}{3}\ \text{cm}\]
This is not $$\frac{88}{3}\ \text{cm}$$.
Step 2 – Reason: R is true. The formula given in the reason correctly gives the arc length for a circle of radius $$r$$ and central angle $$\theta$$.
