What is Velocity?
Velocity is an idea of how fast or slow an object is moving. The velocity of an object can be defined as the rate of change of the object’s position with respect to a frame of reference and time. Velocity is represented by v. It is a vector quantity, which means it depends on both direction and magnitude. The SI unit of velocity is meter per second (ms-1), mph, ft/s are other units of velocity. The dimension of velocity is [LT−1].
The velocity at which motion starts is called the initial velocity. It is represented by u. It’s SI unit is meter per second (m/s).
The velocity at which motion ends is called the final velocity. It is represented by v. It’s SI unit is meter per second (m/s).
Difference between Velocity and Speed
|Velocity tells the direction of the movement of the moving body.||It tells a measure of how quickly something is moving.|
|It is a vector quantity.||It is a scalar quantity.|
|It is the rate of change of displacement.||It is a rate of change of distance.|
Relative velocity is the vector difference between the velocities of two bodies. The concept of relative velocity is used to calculate the velocities of stars and asteroids with respect to the earth’s velocity.
Average velocity is the rate at which an object changes its position from one place to another.
It’s SI unit is meters per second. It is a vector quantity.
Instantaneous velocity is the rate of change of position for a time interval which is very small (almost zero). It’s SI unit is meters per second. It is a vector quantity.