A ball with a mass of 360 g is projected vertically by a spring loaded contraption. The spring in the contraption has a spring constant of 15 (kg)/s^2 and was compressed by 4/3 m when the ball was released. How high will the ball go?

1 Answer
Apr 25, 2018

The height reached by the ball is =3.78m

Explanation:

![http://www.mwit.ac.th](https://useruploads.socratic.org/BDdx3oLBRcinM95cLQLj_spring%20pot%20energy.gif)

The spring constant is k=15kgs^-2

The compression of the spring is x=4/3m

The potential energy stored in the spring is

PE=1/2kx^2=1/2*15*(4/3)^2=13.33J

This potential energy will be converted to kinetic energy when the spring is released and to potential energy of the ball

KE_(ball)=1/2m u^2

Let the height of the ball be =h

The acceleration due to gravity is g=9.8ms^-2

Then ,

The potential energy of the ball is PE_(ball)=mgh

Mass of the ball is m=0.360kg

PE_(ball)=13.33=0.360*9.8*h

h=13.33*1/(0.360*9.8)

=3.78m

The height reached by the ball is =3.78m