circular functions

Question

Calculate the arc length that subtends an angle of 1.64 radians at the centre of a circle with radius 20 m.

Answer 1

arc length = radius x radians = 20 x 1.64 = 32.8 m

arc length = angle times radius when the angle is measured in units of radians

if the angle were 2pi, the the arc length would be the circumference, 2pi(radius) is the formula for the circumference of a circle.