Chapter 11, Problem 68PP

Figure 11.22 shows a demonstration gyroscope, consisting of a solid disk mounted on a shaft. The disk spins about the shaft on essentially frictionless bearings. The shaft is mounted on a stand so it’s free to pivot both horizontally and vertically. A weight at the far end of the shaft balances the disk, so in the configuration shown there’s no torque on the system. An arrowhead mounted on the disk end of the shaft indicates the direction of the disk’s angular velocity.

FIGURE 11.22 A gyroscope (Passage Problems 65–68)

If the system is precessing, and only the disk’s rotation rate is increased, the precession rate will

1. a. decrease.
2. b. increase.
3. c. stay the same.
4. d. become zero.