Which of the following bearings is designed with a grooved race in both the outer and inner members?

If P = equivalent dynamic load (N), Fr = radial load (N), Fa = axial or thrust load (N), V = race-rotation factor, and X and Y are radial and thrust factors respectively, then the expression for the equivalent dynamic load is given by:

The basic dynamic load rating (dynamic load-carrying capacity) of a rolling element bearing is defined as the constant radial load which a group of apparently identical bearings can endure for a rating life of how many revolutions?