# Acceleration

Written by Jerry Ratzlaff on . Posted in Classical Mechanics

Acceleration, abbreviated as a, is the rate of change of velocity with time.  Like velocity, this is a vector quantity that has a direction as well as a magnitude.  Whenever a mass experiences a force, an acceleration is acting.  An increase in velocity is commonly called acceleration while a decrease in velocity is deceleration.  Acceleration is a vector quantity having magnitude and direction, some of these include displacement, drag, force, lift, momentum, thrust, torque, velocity and weight.

## Acceleration Types

• Angular Acceleration  -  An object is the rate at which the angle velocity changes with respect to time.
• Centripetal Acceleration  -  The change in the velocity, which is a vector, either in speed or direction as an object makes its way around a circular path.
• Constant Acceleration  -  An object is the constant rate in a straight line at which the velocity changes with respect to time.
• Uniform Acceleration  -  When an object is traveling in a straight line with a uniform increase in velocity at equal intervals of time.
• Non-uniform Acceleration  -  When an object is traveling with a uniform increase in velocity but not at equal intervals of time.

## Acceleration formula

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

### Where:

 Units English Metric $$\large{ a }$$ = acceleration $$\large{\frac{ft}{sec^2}}$$ $$\large{\frac{m}{s^2}}$$ $$\large{ t }$$ = time $$\large{sec}$$ $$\large{s}$$ $$\large{ \Delta v }$$ = velocity differential $$\large{\frac{ft}{sec}}$$ $$\large{\frac{m}{s}}$$ $$\large{ v_i }$$ = initial velocity $$\large{\frac{ft}{sec}}$$ $$\large{\frac{m}{s}}$$ $$\large{ v_f }$$ = final velocity $$\large{\frac{ft}{sec}}$$ $$\large{\frac{m}{s}}$$

## Related formula

 $$\large{ a = \frac{ F }{ m } }$$ (Force)

### Where:

$$\large{ a }$$ = acceleration

$$\large{ F }$$ = force

$$\large{ m }$$ = mass