The chord ST of a circle is equal to the radius r of the circle. Find the length of arc ST
-
A.
(frac{pi r}{3}) -
B.
(frac{pi r}{2}) -
C.
(frac{pi r}{12}) -
D.
(frac{pi r}{6})
Correct Answer: Option A
Explanation
(frac{ frac{r}{2}}{r}) Sin (theta) = (frac{1}{2})
(theta) = sin(^{-1}) ((frac{1}{2})) = 30(^o) = 60(^o)
Length of arc (minor)
ST = (frac{theta}{360}) x 2(pi r)
(frac{60}{360} times 2 pi times r = frac{pi}{3})
There is an explanation video available below.