Question

A particle moves along a circle of radius $\left(\frac{20}{\pi }\right)$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 begun, the tangential acceleration is?

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

Answer 1

Answer: (A)

$40m/s^2$

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

$=S=\frac{2\times 2\pi \times 20}{\pi }=80m.$

Now by using the formulae

$v^2-u^2=2aS$

$(80{)}^2=2a80$

$a=80\times \frac{80}{2}\times 80=40m{s}^{-2}$