(I) Work and energy are viewed as the cornerstones of
science. (II) To a scientist, work is defined as the force
applied to an object multiplied by the distance it moves
in response. (III) All of the energy in a physical system
would be available to do useful work. (IV) On the other
hand, a system’s energy can be described as its ability
to do work. (V) For example, a truck’s engine is able to
liberate the chemical energy stored in fuel and then use
it to do work on the truck and make it move.