Question

Define radius of a circle.

Answer 1

Define radius of circle with appropriate figure

A segment joining the center of a circle to any point on the circumference of the circle is called the radius of the circle.

The radius of the circle is generally denoted by $r$.

Radius of a circle is half of the diameter of the circle.

$\Rightarrow r=\frac{d}{2}$, where $d$ is the length of the diameter of the circle.