Question

In the given figure, $a=15m/s^2$ represents the total acceleration of a particle moving in the clockwise direction in a circle of radius $R=2.5m$ at a given instant of time. The speed of the particle is

• A. $6.2m/s$
• B. $4.5m/s$
• C. $5.0m/s$
• D. $5.7m/s$

Answer 1

The correct option is D $5.7m/s$

Given : $R=2.5m$, $a=15m/s^2$
From figure, centripetal acceleration
$a_c=a\cos {30}^o=15\times 0.866=13m/s^2$
Using $a_c=\frac{v^2}{R}$
$13=\frac{v^2}{2.5}$
$⟹v=5.7m/s$