Question

A particle moves along a circle of radius $2m$ with a constant speed of $8m/s$. It covers the quarter of circle in sec?

• A. $\frac{\pi }{16}$
• B. $\frac{\pi }{8}$
• C. $\frac{\pi }{4}$
• D. $\frac{\pi }{2}$

Answer 1

Answer: (B)

$\frac{\pi }{8}$

Given :

Radius of the circle $=2m$

Speed of the particle $=8m/s$

To find : Time taken to cover the quorter of circle.

the distance covered to complete the quorter of circle is :

$d=\frac{circumference}{4}=\frac{2\pi r}{4}$

$\Rightarrow \frac{2\pi \times 2}{4}$

$\Rightarrow \pi .m$

The time taken by the particle to cover the distance.

$t=\frac{d}{v}$

$\Rightarrow \frac{\pi }{8}sec$

Option (B) is correct.