A gyroscope takes 3.8 s to precess 1.0 revolution about a vertical axis. Two minutes later, it takes only 1.9 s to precess 1.0 revolution. No one has touched the gyroscope. Explain.
Solution 29DQ Introduction We have to discuss why the precession speed of gyroscope increases, even when nobody touches it. Step 1 The precession speed of gyroscope increases with the decrease of its spinning speed. Now when the gyroscope rotates, because of the viscosity of the water, the surrounding air resists the spinning motion of the gyroscope. Hence the angular velocity of the spin decreases, and so the precession speed increases. That’s why after some time the 1.0 revolution of precession takes 1.9 s instead of 3.8 s.