
17Physical Foundation of Interior Ballistics
they are placed in contact with them, thus giving up some of their energy and increasing
the energy of the contacted substance. Temperature is a sensible measure of an object’s
internal energy.
Work is a means of increasing an object’s energy by application of a force through a dis-
tance. This method of energy transfer can create either potential energy, as in compressing
a spring, or kinetic energy as applied to a free, rigid mass. While the equations for heat
transfer can be the subject of entire texts (e.g., [9]), work can be dened through the vector
equation
(2.29)
where
W is the work don ...