Question

On the unit circle, an arc of length 2 subtends an angle, β. What is the radian measure of β?

Answer 1

2rad

Explanation:

Answer 2

`(d)\ \beta = 2\ rad`

Explanation:

Given

`L =2` -- length of the arc

`r = 1` --- radius of a unit circle

`\beta =` the subtended angle

Required

Find
`\beta`

The length of an arc is:

`L = r * \beta`

This gives:

`2 = 1 * \beta`

`2 = \beta`

Make
`\bets`
`\beta` the subject

`\beta = 2`

Hence:

`\beta = 2\ rad`