# Velocity

Written by Jerry Ratzlaff on . Posted in Classical Mechanics

Velocity, abbreviated as v or VEL, is the rate of change or displacement with time.  Velocity is a vector quantity having magnitude and direction. The scalar absolute value of magnitude of the velocity vector is the speed of the motion.  Velocity is not speed, they do not mean the same thing.

Velocity is a vector quantity having magnitude and direction, some of these include acceleration, displacement, drag, force, lift, momentum, thrust, torque, and weight.

### Velocity Formula

(Eq. 1)  $$\large{ v = \frac { d }{ t } }$$

(Eq. 2)  $$\large{ v = v_i + a \; t }$$

Where:

$$\large{ v }$$ = velocity

$$\large{ a }$$ = acceleration

$$\large{ d }$$ = displacement

$$\large{ v_i }$$ = initial velocity

$$\large{ t }$$ = time

Solve for:

$$\large{ v_i = v - a \; t }$$

$$\large{ t = \frac { d }{ v } }$$

## Air Velocity

Air velocity is the measurement of air speed, typically in feet or meters per minute.