The chord length of a chord made on an arc of a circle is equal to the radius of the circle. The length of the arc is........(in units). if the radius of the circle is 21 units. (take π = 22/7)
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Correct answer: C
Explanation
The correct answer is Option 3 i.e 22.
The radius of the circle as r = 21 units
The chord length is r = 21 units, which is given to be equal to the radius.
For an isosceles triangle, θ is 120 or 2π/3 radians as this configuration yields a chord length equal to the radius in a circle.
We know that,
arc length(s) = rθ
⇒ s = 21 × π × 1/3
⇒ 21 × 22/7 × 1/3
⇒ 7 × 22/7
⇒ 22
So, the length of the arc is 22 units.