CDi = CLαi
CDi is the Induced Drag Coefficient
CL is the Lift Coefficient
αi is the Induced Angle of Attack
Induced Drag is an Aerodynamic Drag force that occurs whenever a moving object redirects the airflow coming at it. This drag force occurs in airplanes due to Wings or a Lifting body redirecting air to cause Lift and also in cars with airfoil wings that redirect air to cause a Downforce.