A ball with a mass of #120 g# is projected vertically by a spring loaded contraption. The spring in the contraption has a spring constant of #8 (kg)/s^2# and was compressed by #3/5 m# when the ball was released. How high will the ball go?

1 Answer
Apr 10, 2018

The height is #=1.22m#

Explanation:

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The spring constant is #k=8kgs^-2#

The compression is #x=3/5m#

The potential energy in the spring is

#PE=1/2*8*(3/5)^2=1.44J#

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=0.120kg#

#PE_(ball)=1.44=0.120*9.8*h#

#h=1.44*1/(0.120*9.8)#

#=1.22m#

The height is #=1.22m#