An arc of length 10.8 cm subtends an angle of 1.2 radians at the centre of a circle. Calculate the radius of the circle.
-
A.
12.6 cm -
B.
12.0 cm -
C.
9.6 cm -
D.
9.0 cm
Correct Answer: Option D
Explanation
Length of arc (in radians) = (r theta)
(10.8 = 1.2r)
(r = frac{10.8}{1.2} = 9.0 cm)