That equation indicates that a small amount of mass can be converted into a huge amount of energy. For example, the atomic bomb that was dropped on Hiroshima had a force of about 13-18 thousand tons of TNT. But in that explosion, only about 1/3 the mass of a U.S. dime was actually converted into energy. (And most of the force resulted from the rapid unbinding of tightly packed neutrons in the atomic nuclei of uranium.)