In the given figure, the length of arc AB is equal to twice the length of radius r of the circle. Find the area of sector OAB in terms of the radius r.
Answer & explanation
Correct answer: option 4
We know that,
l = r × θ
Area of an arc = \(\frac{ θ }{360 }\) × πr2
According to the question,
Length of the arc AB = 2r
Here, we have length of the arc = 2r
= l = r × θ
= 2r = r × θ
= θ = 2
Area of the sector = \(\frac{ θ }{360 }\) × πr2
= \(\frac{ 2 }{360 }\) × 180 × r2 = r2