An artillery shell explodes in midair and breaks up into many fragments. Which of the following statements are true regarding conditions immediately before and immediately after the explosion:
I. The total momentum of the fragments is equal to the original momentum of the shell.
II. The total kinetic energy of the fragments is equal to the original kinetic energy of the shell.
A) Statement I only
B) Statement II only
C) Both Statement I and Statement II
D) Neither statement is true.

Question

Quizplus · Accepted Answer

Conservation of momentum states that in the absence of external forces, the total momentum of a system remains constant. Therefore, immediately before the explosion, the momentum of the shell must be equal to the momentum of all of its fragments after the explosion. Thus, statement I is true.

However, the total kinetic energy is not necessarily conserved in an explosion. Some of the original kinetic energy of the shell may be converted into other forms of energy, such as thermal or potential energy. Therefore, statement II is not necessarily true.

An Artillery Shell Explodes in Midair and Breaks Up into Many