Motion in a plane

Motion of the body can be represented in many ways according to the vision of observer. The motion of an object is called two dimensional, if two of the three co-ordinates required specifying the position of the object in space, change with respective to time. In such a motion, the object moves in a plane. For example, a billiard ball is moving over the billiard table, an insect crawling over the floor of a room, earth revolving around the sun etc.  

The motion of a projectile is a two-dimensional motion. So, it can be discussed in two parts. Horizontal motion and vertical motion. These two motions take place independent of each other. This is called the principle of physical independence of motions. And force is the main factor and root cause for the motion of any body. All motions may not be depends on the applied external force & some bodies may move with help of their individual possession of energies.

Body is in motion means it will possess so many dynamic parameters & it will depend on those parameters throughout its entire journey. Some of the basic dynamic parameters of the mobbing body are velocity, acceleration & momentum etc. All these parameters will decides the motional behavior of the body. And the motion will be representing in different kinds of ways and the representation will be very fine enough to analyze the behavior of body. Dynamic co-ordinate systematic representation of body which is in motion is the basement for logical analysis and key for the complex motional bodies.