Speed || Velocity || Acceleration

 Speed:

Change in distance per unit time is called speed.

It is the rate of change of distance.

It is Scalar quantity and its S.I unit is m/s. (meter per second).

Velocity:

 It is defined as the rate of change of displacement.

Change in displacement per unit time is called velocity.

It is Vector quantity.

 Its S.I unit is m/s (meter per second) or m s-¹

.

 Its dimension is M⁰LS-¹

.

Average Velocity : The ratio of total displacement covered by a total time is called average

velocity.

Uniform Velocity : When a body covers an equal displacement with an equal interval of

time is called constant or uniform velocity.

 Non Uniform Velocity: When a body covers unequal displacement in unequal Interval of

time is called non uniform or variable velocity.

 Velocity is a vector quantity because it has magnitude as well as direction.

 If there are changes in displacement or time then the velocity will change in acceleration.

Acceleration: It is defined that the velocity of a body covered a distance by its particular

direction in unit time

 It can be changed by a change in its magnitude or its direction or both.

 It is the rate of change of velocity.

 Change in velocity per unit time.

 If the velocity of a body is decreasing the acceleration is negative acceleration is also

known as deceleration or retardation.

 If the velocity is increasing the acceleration is positive.

 Its S.I Unit is m/ s²

 or ms-²