A ball with a mass of #150 g# is projected vertically by a spring loaded contraption. The spring in the contraption has a spring constant of #18 (kg)/s^2# and was compressed by #7/5 m# when the ball was released. How high will the ball go?

1 Answer
May 23, 2017

Answer:

The height is #=12m#

Explanation:

enter image source here

The spring constant is #k=18kgs^-2#

The compression is #x=7/5m#

The potential energy in the spring is

#PE=1/2*18*(7/5)^2=17.64J#

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 #

Then ,

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

#PE_(ball)=17.64=0.15*9.8*h#

#h=17.64*1/(0.15*9.8)#

#=12m#