newton
In S.I system of units, the unit of force is Newton (briefly written as N). A Newton may be defined as the force, while acting upon a body of mass 1 kg, produces an acceleration of 1m/s2 in the direction of which it acts.
1 N = 1 kg x 1 m/s2 = 1 kg-m/s2
joule
Whenever a force (F) acts on a body and the body undergoes a displacement (x) in the direction of the force, then the work is said to be done.
Mathematically, Workdone = F.x = Force x Displacement.
The unit of work depends upon the unit of force and the displacement. In S.I. system of units, the practical unit of work is N-m. It is the work done by a force of 1 newton when it displaces a body through 1 metre. The work of 1 N-m is known as joule (briefly written as J), such that 1 N-m = 1 J.
