Question

A particle starts moving along a circle of radius $\left(20/\pi \right)$. If the velocity of the particle is 80 m/s at the end of the second revolution after motion has began,the tangential acceleration in $m/s^2$ is :

• A. 60
• B. 40
• C. 15.6
• D. 13.2

Answer 1

The correct option is B 40

It is given that,

Radius,$R=\frac{20}{\pi }$

As the particle has made 2 revolutions along a circle. Then the displacement is, $s=2\times 2\pi r=80m$

Velocity is, $v=80m/s$

Using the equation of motion as

$v^2-u^2=2as$

${80}^2-0=2a\times 80$

so the value of acceleration is:

$a=40m/s^2$