Heat and Thermodynamics

1.4 Conservative Field of Force

A field of force is the space throughout which force is experienced. Thus, the space surrounding the Earth is its gravitational field. Any piece of matter placed in this field is attracted towards the Earth. The field is said to be conservative if the work done in displacing a body from one position to another and back to the initial position is zero. This means that the work done in moving a body from one position A to another position B is independent of the path along which the body is carried. This can be proved as follows:

Let a particle be carried in a conservative field of force from A to B along the path ANB and back to A along the path BQA (Fig. 1.3). Let the same particle be carried from A to B along ...