Tidal locking is what makes the Moon rotate about its own axis at the same rate that it revolves around Earth
Using as a model of a moon two identical masses of mass m connected by a light rod, explain how the forces on the masses would tend to keep this satellite in a fixed orientation.
Suppose that the masses are oriented so that the rod is along a radial line from the planet. The forces on the two masses are unequal, but they are lined up, so there is no tendency to turn. If the rod is turned a small amount, the mass nearer the planet is attracted with a larger force, so there is a net torque directed so as to orient the satellite the way it was originally. If the rod is turned through 90°, the torques are again in equilibrium, but this is an unstable equilibrium because a small displacement away from that position will produce a torque in the same direction as the rotation of the rod.
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How many moons does earth have
A) none B) one C) two D) three E) four
A large school district has 300 school buses. If each school bus is used 3.0 hours each day, the average speed of the school buses is 15 mi/h, and the fuel economy of the buses is 10 mi/gal
How much does it cost to run these buses for 22 school days if gasoline costs $4.10 a gallon? A) $60,000 B) $120,000 C) $180,000 D) $240,000
Light strikes a 5.0 cm thick sheet of glass with index of refraction 1.50 at an angle of incidence in air of 50°. (a) What is the angle of refraction in the glass? (b) After traveling through the glass the light re-emerges into the air
What is the final angle of refraction in air? (c) Determine the amount its path is displaced when it leaves the glass from what it had been before entering the glass.
If heavier elements are more stable when they have more neutrons, what happens to the heaviest elements?
a. They have very large nuclei to sustain the number of neutrons needed for stability. b. Above a certain atomic mass, there are no stable elements. c. For high enough atomic mass, there is no longer a rule to determine which nuclei are stable. d. The curve reverses and the nuclei of the heaviest elements are more even matches of protons and neutrons. e. The curve reverses completely and the nuclei of the heaviest elements are stable with many more protons than neutrons.