 # The speed of an object in a particular direction is called

The speed of an object in a particular direction is called velocity.

## Definition

Velocity can also be defined as the rate of change of the object’s position with respect to a frame of reference and time.  Velocity in basics can be said as speeding in a specific direction.

## Properties of velocity

• It is a vector quantity
• Since it is a vector quantity both magnitude (speed) and direction are required to define velocity
• The SI unit of velocity is meter per second. It is denoted as ms-1
• Other units of velocity are mph, ft/s
• The dimension of velocity is  LT−1
• A body is said to accelerating if there is a change in magnitude or the direction in the velocity of a body
• Velocity is the prime indicator of the position as well as the rapidity of the object

## Example

A train going towards south with an average speed of 50 km/h will have a velocity of 50km/h, north. An object going straight in a particular direction is considered to have velocity.