Question

Carry is running over a circular track of radius $10m$. If he runs $2m$ in $1\text{second}$. Find the angle substended by carry at the center of circular track in $1$ second.

• A. $2\text{rad}$
• B. $0.2\text{rad}$
• C. $5\text{rad}$
• D. $0.5\text{rad}$

Answer 1

The correct option is B $0.2\text{rad}$

We know
$\theta =\frac{l\text{(Length of arc)}}{r\text{(Radius of circle)}}$
In $1\text{second}$ carry covers $2m$ of circular track.
$\therefore \text{Length of arc =}2m$
$\text{Radius of circular track =}10m\text{..(given)}$
$\therefore \theta =\frac{l}{r}=\frac{2m}{10m}=0.2rad$