Question

Determine the length (to 1 decimal place) of the arc that subtends an angle of 2.8 radians at the centre of a circle with radius 12 cm.

13.3 cm

33.6 cm

148.0 cm

16.8 cm

Answer 1

33.6 cm

Explanation:

We can use the formula for arc length to solve this.

`s=r\theta`

Where

s is the arc length

r is the radius

`\theta` is the angle subtended by the arc (in radians)

The problem gives us theta = 2.8 radians and radius of the circle as 12 cm. We plug these into the formula and figure out the arc length (to 1 decimal place):

`s=r\theta\\s=(12)(2.8)\\s=33.6`

2nd answer choice is right.