Two hypothetical discoveries in Part A deal with moons that, like Earth's moon, are relatively large compared to their planets. Which of the following best explains why finding 1 planet with such a moon is consistent with the nebular theory, while finding 6 planets with such moons is not consistent?
a. Unusually large moons form in giant impacts, which are relatively rare events.
b. The nebular theory says that only planets at least as large as Earth can have large Moons, and 6 Earth-size planets would not be likely to form in one solar system.
c. The nebular theory holds that moons of any size should be rare, so finding 1 is not too surprising but finding 6 would be very surprising.
Answer : a. Unusually large moons form in giant impacts, which are relatively rare events.
You might also like to view...
Magnetic Field of a Long Wire: Three long parallel wires each carry 2.0-A currents in the same direction. The wires are oriented vertically, and they pass through three of the corners of a horizontal square of side 4.0 cm. What is the magnitude of the magnetic field at the fourth (unoccupied) corner of the square due to these wires? (?0 = 4? × 10-7 T ? m/A)
A. 1.2 µT B. 2.1 µT C. 12 µT D. 21 µT E. 0 T
Based on current evidence, a supercluster is most likely to have formed in regions of space where
A) the density of dark matter was slightly higher than average when the universe was very young. B) there was an excess concentration of hydrogen gas when the universe was very young. C) supermassive black holes were present in the very early universe. D) the acceleration of the expansion was proceeding faster than elsewhere.
In an RC circuit, what fraction of the final energy is stored in an initially uncharged capacitor after it has been charging for 3.0 time constants?
A. 0.84 B. 0.90 C. 0.75 D. 0.60 E. 0.03
Kepler improved the Copernican planetary hypothesis by
a) putting the Sun at the center of our solar system. b) putting Earth at the center of our solar system. c) suggesting that the Sun rotates on its axis. d) determining the true shapes of the planetary orbits.