An Object Initially at Rest Suddenly Explodes in Two Fragments $2.6 \mathrm {~kg}$

Multiple Choice

An object initially at rest suddenly explodes in two fragments of masses $2.6 \mathrm {~kg}$ and $3.3 \mathrm {~kg}$ that move in opposite directions. If the speed of the first fragment is $3.6 \mathrm {~m} / \mathrm { s } \text {, }$ find the internal energy of the explosion.

A) 30 J
B) 30 kJ
C) 38 J
D) 38 kJ