To account for mechanical transmission losses in the gearbox and bearings, apply an efficiency factor ( ), typically between 0.75 and 0.90.

P=Np⋅ρ⋅N3⋅Da5cap P equals cap N sub p center dot rho center dot cap N cubed center dot cap D sub a to the fifth power Based on the equivalent bending moment ( Memcap M sub e m end-sub ) and the material's yield stress.