# What is Motion in Physics? | Definition, Types – Motion in a Straight Line

Motion Meaning:
If an object changes its position with respect to its surroundings with time, then it is called in motion.

We are giving a detailed and clear sheet on all Physics Notes that are very useful to understand the Basic Physics Concepts.

## Motion in Physics | Definition, Types – Motion in a Straight Line

Types of Motion in Physics
1. One Dimensional Motion Definition :
If only one out of three coordinates specifying the position of the object changes with respect to time, then the motion is called one dimensional motion or rectilinear motion.

For instance, motion of a block in a straight line, motion of a train along a straight track, a man walking on a level and narrow road and object falling under gravity etc.

2. Two Dimensional Motion Definition:
If only two out of three coordinates specifying the position of the object change with respect to time, then the motion is called two dimensional motion.

A circular motion is an instance of two dimensional motion.

3. Three Dimensional Motion Definition:
If all the three coordinates specifying the position of the object change with respect to time, then the motion is called three dimensional motion. A few instances of three dimension at motion are flying bird, a flying kite, the random motion of gas molecule etc.

Motion in a Straight Line Topics: