A gyroscope, a uniform disc of radius R = 5.0 cm at the end of a rod of length l = 10 cm (Fig. 1.73), is mounted on the floor of an elevator car going up with a constant acceleration w = 2.0 m/s2. The other end of the rod is hinged at the point O. The gyroscope precesses with an angular velocity n = 0.5 rps. Neglecting the friction and the mass of the rod, find the proper angular velocity of the disc.