Kinematics

Kinematics

1. Displacement

2. Speed

3. Uniform Speed

4. Velocity

5. Uniform Velocity

6. Variable Velocity

7. Average Velocity

8. Uniform Acceleration

9. Average Acceleration

1. Displacement

A vector quantity, which signifies the least distance between two points in a particular direction, is called displacement.

2. Speed

The distance travelled by an object in unit time is called the speed of the object. It is a scalar quantity.

Speed = Total distance travelled/Time taken

v=S/T

The unit of speed in SI System is meter / second or m/s.

3. Uniform Speed

If a moving body covers equal distances in equal intervals of time, however small, the intervals maybe in any direction, then the speed of the moving body is called Uniform Speed.

4. Velocity

The rate of change of displacement is called velocity, It is a vector quantity

or

The speed of a body in a definite direction is called its velocity. Mathematically it can be expressed as:

V = S / t

5. Uniform Velocity

If the displacements covered by a body in equal intervals of time are same then the body is said to move with a uniform velocity.

6. Variable Velocity

If the displacements covered by a body in equal intervals of time are not the same, the velocity of the body is variable. The variation in the velocity can either be due to the change in its magnitude or direction or both.

For example a body moving with variable speed in a straight line has a variable velocity although its direction of motion remains the same, and a body moving in a circle with uniform speed has variable velocity because at every moment its direction is changing.

7. Average Velocity

The average velocity of a moving body is obtained by dividing its total displacement by the total time taken.

Average Velocity = Total displacement/ Total time

The average velocity of a moving body is also obtained by dividing the sum of the initial and the final velocities by 2.

V = Vi+Vf / 2

Where Vi and Vf are the initial and the final velocity respectively.

8. Uniform Acceleration

If the velocity of a body moving along a straight line changes uniformly in equal intervals of time, however short the Intervals may be, the acceleration so produced is called uniform accelerations

9. Average Acceleration

The ratio between the total change in velocity and time is called average acceleration.