A simply supported circular shaft of 10 m length is subjected to a 20 kN concentrated point load at its mid-span. The shaft transmits 30 kW of power at a speed of 180 rpm. If the maximum permissible shear stress in the shaft is restricted to 20 MPa, calculate the required diameter of the shaft based on the maximum shear stress theory.

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: