Question

A $0.5kg$ ball moves in a circle of radius $0.4m$ at a velocity of $4m/s$. The centripetal force on the ball is

• A. 10 N
• B. 20 N
• C. 40 N
• D. 80 N

Answer 1

Answer: (B)

$F=\frac{m{v}^2}{r}$
$F=\frac{0.5\times 4\times 4}{0.4}$
$F=\frac{8.0}{0.4}$
$=\frac{80}{4}=20N$