Question

Length of an arc of a circle with radius $r$ and central angle $\theta$ is(angle in radians):

• A. $\frac{r\times \theta }{{360}^o}$
• B. $\frac{r\times \theta }{{180}^o}$
• C. $\frac{r\times \theta }{{90}^o}$
• D. $r\times \theta$

Answer 1

Answer: (D)

$r\times \theta$

Let $r$ be the radius of a circle and $\theta$ be the central angle

Length of an arc of the sector $=r\times \theta$

Hence, length of an arc of a circle $=r\times \theta$.