Physics: Motion in a Straight Line

If an object changes its position with respect to its surroundings with time, then it is called motion. In simpler words, a change in position over time is called motion. Motion in a straight line is linear motion and uses only one dimension.

Linear motion is the most simple kind of motion. As Newton's first law of motion suggests, an object will either be in rest or continue to move in a straight line with uniform velocity unless and until an external force is applied.

Types of Linear Motion:

1. Uniform Linear Motion with constant velocity or zero acceleration

• A body is said to have uniform acceleration if the rate of change of its velocity remains constant.
• Basically, the object covers equal distance in equal time intervals.
• Example: If a car travels at 60km/h then it will cover 1km/minute. The motion of the car is uniform.

1. Non-Uniform Linear Motion with variable velocity or non-zero acceleration.

• The body has non-uniform motion when the velocity of a body changes by unequal amounts in equal time intervals.
• Example: A boy kicking a football 4 meters in his first attempt, 6 meters in second attempt, 9 meters in the third attempt, and so forth.

Equations of Motion:

Note:- DON'T CONFUSE LINEAR MOTION WITH GENERAL MOTION BECAUSE GENERAL MOTION HAS BOTH MAGNITUDE AND DIRECTION GIVEN IN VECTOR QUANTITIES.