Question

Find the arc length of the semicircle. Either enter an exact answer in terms of \piπpi or use 3.143.143, point, 14 for \piπpi and enter your answer as a decimal.

Answer 1

The answer is 15.7

Explanation:

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Answer 2

`3.14r` or
`\pi r`

Explanation:

Given:

A semicircle.

To find:

Arc length of the semicircle = ?

Solution:

Formula for angle subtended by an arc on the center of circle is given as:

`\theta = (l)/(r)`

where
`l` is the arc length and

`r` is the radius of semicircle.

Angle of full circle is
`2\pi`

So, angle of semicircle =
`\pi`

Using the formula, we can see that:

`l = \theta * r`

`\Rightarrow l = \pi * r\\\\OR\\\Rightarrow l = 3.14r`

So, the answer is:

Arc Length of semicircle =
`3.14r` or
`\pi r`