Question

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

• A. $160\pi m/s^2$
• B. $40\pi m/s^2$
• C. $40m/s^2$
• D. $640\pi m/s^2$

Answer 1

The correct option is C $40m/s^2$

Total distance travelled after $2$revolutions $=2\times 2\pi r$

$=2\times 2\times \pi \times \frac{20}{\pi }=80m{v}^2-u^2=2as,u=0\frac{v^2}{2s}=a\Rightarrow a=\frac{6400}{2\times 80}=40m/s^2$