Applied mechanics is divided into two main branches:

（a) **Statics**

（b)**Dynamics**

（a) **Statics**: It is that branch of applied mechanics which deals with the forces and their effects

while acting upon the bodies at rest or in equilibrium.

For example, the study of the equilibrium of a book lying on a table, forces in various members of a truss and tensions in the ropes of pulleys, etc.

（b) **Dynamics**: It is that branch of applied mechanics which deals with the forces and their

effects while acting upon the bodies in motion.

For example, the study of different forces acting on the various parts of a watch.

**Dynamics is further sub-divided into two branches :**（i) Kinematics

（ii)Kinetics

（i) **Kinematics**: It is that branch of dynamics which deals with bodies in motion without

considering the forces which cause that motion.

For example, a freely falling body under gravity and relative velocity of boat and river.

（ii) **Kinetics**: It is that branch of dynamics which deals with the bodies in motion considering

the forces which cause that motion.

For example, acceleration and retardation of a moving body.