# Air Resistance

Written by Jerry Ratzlaff on . Posted in Classical Mechanics

Air resistance is a force that opposes an object as it moves through the air.

### Air Resistance formula

(Eq. 1)  $$\large{ F_a = kv^2 }$$

(Eq. 2)  $$\large{ F_a = \frac{\rho C_d A}{2} v^2 }$$

Where:

$$\large{ F_a }$$ = force of air resistance or drag

$$\large{ A }$$ = area cross section of the object

$$\large{ \rho }$$  (Greek symbol rho) = atmosphere density object moves through

$$\large{ C_d }$$ = drag coefficient

$$\large{ k }$$ = a constant that collects the effects of area, density, and drag

$$\large{ v }$$ = velocity of the moving object