Question

A particle is moving along a circular path of radius $5\,m$ with uniform speed $5\, m/s$. What will be the average acceleration -when the particle completes half revolution?

• A. $ \frac{10}{\pi }m/s^{2} $
• B. $ 10\,m/s^{2} $
• C. $ 10\pi \,m/s^{2} $
• D. zero

Answer 1

Answer: (A)

Change in velocity when the particle completes half revolution is
$\Delta v=5-(-5)=10 \,m / s$
Time taken in completing half revolution is
$T=\frac{\pi r}{v}=\frac{\pi \times 5}{5}=\pi $ second
Hence, average acceleration when particle completes half revolution
$a_{a v}=\frac{\Delta v}{T}=\frac{10}{\pi} m / s ^{2}$