निम्नलिखित में से सोमरफेल्ड संख्या (Sommerfeld number) की इकाई कौन सी है?

The dynamic load-carrying capacity of a radial bearing is defined as the constant radial load that the bearing can withstand for a rating life of how many revolutions?

If P = equivalent dynamic load, Fr = radial load, Fa = axial or thrust load, V = race-rotation factor, and X and Y are radial and thrust factors respectively, then the correct expression for equivalent dynamic load on a bearing is: