Question

A ball of mass 100 g is placed on a compressed spring. The spring has stored
5 J of potential energy due to compression. Calculate the velocity of the ball after the spring is released.

• A. 25 m/s
• B. 10 m/s
• C. 20 m/s
• D. 5 m/s

Answer 1

The correct option is B 10 m/s

Given,

Potential energy of the spring, PE = 5 J

Mass of the ball, m = 100 g = 0.1 kg

Let velocity and kinetic energy of the ball be v and KE, respectively.

As the potential energy of the spring is converted to kinetic energy of the ball,

KE = PE = 5 J

$\frac{1}{2}m{v}^2$ = 5

$\frac{1}{2}$ × 0.1 × $v^2$ = 5

$v^2$ = 100

v = 10 m/s