This tool calculates the terminal falling velocity of a spherical object moving in the air with gravity pulling the object downwards. The air resistance (drag force) increases with the increasing acceleration of a falling object under gravity. A velocity is reached where the air resistance balances the gravitational acceleration on the object. As a result, the object moves with a constant velocity thereafter which is called terminal falling velocity.

where *m* in the above equation is the object mass, *ρ* is the density of air, *A* is the sphere cross-sectional area, *C _{D}* is the drag coefficient and g is the gravitational acceleration.

Type the required values to get the terminal velocity:

Sphere Diameter (m)

Sphere Density (*ρ _{p}*, kg/m

Air Density (*ρ _{air}*, kg/m

Terminal velocity (m/s)

Drag Coefficient

Reynolds Number