Question

A particle is revolving at $1200 \,rpm$ in a circle of radius $30\, cm$. Then, its acceleration is

• A. $1600\, ms ^{-2}$
• B. $4740 \,ms ^{-2}$
• C. $2370\, ms ^{-2}$
• D. $5055\, ms ^{-2}$

Answer 1

Answer: (B)

Given, $v=1200 \,rpm =\frac{1200}{60}\, rps$,
$r=30\, cm =\frac{30}{100} \,m$
Acceleration of the particle
$=$ Centripetal acceleration $=\omega^{2} r=(2 \pi v)^{2} r$
$=\left(2 \times \frac{22}{7} \times \frac{1200}{60}\right)^{2} \times \frac{30}{100} \approx 4740 \,ms ^{-2}$