Question

A ball of mass 0.25 kg attached to the ends of a strings of length 1.96 m is rotating in a horizontal circle. The string will break, if tension is more than 25 N. What is the maximum velocity with which the ball can be rotated?

• A. 3 m/s
• B. 5 m/s
• C. 9 m/s
• D. 14 m/s

Answer 1

The correct option is D 14 m/s

Centrifugal force in the string is given by

$F=\frac{m{v}^2}{r}$

$v^2=\frac{Fr}{m}$

$v^2=\frac{25\times 1.96}{0.25}=196$

$v=\sqrt{196}=14m/s$