A Toy gun has a spring of force constant ,k. After changing the spring by compressing it through a distance of & the toy releases a shot of mass m vertically upwards. Then the shot will travel a vertical height is equal to

Here the potential energy of the spring will be given to the mass m which is fired from the toy gun∴  K.E.ofmass =12kx2 At highest point, the kinetic energy is converted into potential elrorry, i.e., 12kx2=mgh  or  h=kx2/2mg