Given, mass of the ball, m=4kg Velocity of the ball, v=10m/s Force constant, k=100N/m The length of the spring, x=8m Let x is the compressed length of the spring. Using the work-energy theorem, "It states that kinetic energy of the ball is converted into the stored energy of spring".
mv2
2
=
kx2
2
⇒
4(10)2
2
=
(100)x2
2
⇒x=2m The final length (compressed) of the spring =8−2=6m Hence, the value of x to the nearest integer is 6 .