Question

The radius of a circle is 4 km what is the length of a 180 Arc​

Answer 1

12.56 km

Explanation:

To Find:

• Length of the arc.

Information Provided:

• Radius of the circle is 4 km.
• Degree of the arc is 180°.

Formulas:

• To find length of the required arc

`\frac{x}{ {360}^(o) } * 2\pi \: r`

Solution:

Given,

Radius of the circle (r) = 4 km

Angle of the given arc (x) = 180°

Therefore,

Length of the given arc

`= \frac{x}{ {360}^(o) } * 2\pi \: r`

• [On putting the values]

`= (\frac{ {180}^(o) }{ {360}^(o) } * 2 * 3.14 * 4) \: km`

• [On simplifying]

`=( (1)/(2) * 2 * 3.14 * 4) \: km`

• [Further simplification]

= 12.56 km

Hence,

The required length of the given arc is 12.56 km (Ans)