A ball with a mass of 70 g is projected vertically by a spring loaded contraption. The spring in the contraption has a spring constant of 5 (kg)/s^2 and was compressed by 7/6 m when the ball was released. How high will the ball go?

1 Answer
Apr 6, 2018

The height is =4.96m

Explanation:

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

The spring constant is k=5kgs^-2

The compression is x=7/6m

The potential energy in the spring is

PE=1/2*5*(7/6)^2=3.40J

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=0.070kg

PE_(ball)=3.40=0.070*9.8*h

h=3.40*1/(0.07*9.8)

=4.96m

The height is =4.96m