An object that is initially at rest breaks up into two pieces of unequal masses when a spring-loaded device is released. If you compare the kinetic energy of the larger mass to that of the smaller mass immediately after they separate, which of the following statements is correct?
A) The kinetic energy of the larger mass is greater.
B) The kinetic energy of the smaller mass is greater.
C) The kinetic energies of the two masses are equal.
D) The total kinetic energy is zero J.

Question

Quizplus · Accepted Answer

When an object breaks up into two pieces, the total kinetic energy remains the same, but it is divided among the two pieces. Since the masses are unequal, the velocity of the larger mass will be smaller than that of the smaller mass, because the larger mass will experience a smaller force than the smaller mass. Thus, the kinetic energy of the smaller mass will be greater than the kinetic energy of the larger mass.

An Object That Is Initially at Rest Breaks Up into Two