Download Quiz 6 Key

Introduction to Descriptive Astronomy
Quiz # 6
Name_________________________________
1.) The force of gravity is responsible for
A. holding the planets near the Sun.
B. the tides.
C. holding the Moon near the Earth.
D. [All of the above.]
E. [Only two of the above.]
2.) Spring tides
A. occur during the spring.
B. occur about once a month.
C. correspond to the greatest difference between high and low tides.
D. correspond to the least difference between high and low tides.
3.) The point in the orbit of the Moon where it is closest to the Earth is called its
A. aphelion.
B. perihelion.
C. apogee.
D. perigee.
E. zenith.
4.) As the Moon orbits the Earth,
A. the same side always faces Earth.
B. the same side always stays in darkness.
C. the lit side is always the side that faces the Earth.
D. [All of the above.]
E. [Both A and B]
5.) Earth’s surface rocks have a density of about 3,500 kg/m3, while the average density of the planet is about 5,500
kg/m3. From this we infer that
A. Earth’s interior is less dense than surface rocks.
B. Earth’s interior is more dense than surface rocks.
C. Earth is hollow.
D. Earth’s crust is very thick.
6.) The thick, solid layer between the crust and the core of the Earth is called the
A. differentiation layer.
B. mantle.
C. polar cap.
D. equatorial layer.
E. temperate layer.
7.) Differentiation is the
A. melting of volatile elements within a planet.
B. separation, by geologists, of the portions of the Earth (or other objects).
C. sinking of denser material toward the center of planets (or other objects).
D. heat flow from within the Earth.
E. separation of the Earth’s rotational north pole from its magnetic north pole.
8.) Auroras are caused by
A. charged particles impacting on the Earth’s atmosphere.
B. sunlight being reflected by upper layers of the atmosphere.
C. sunlight being refracted by upper layers of the atmosphere.
D. moonlight being refracted and reflected by upper layers of the atmosphere.
E. gravitational attraction of light toward the Earth.
9.) The Earth’s magnetic field
A. originates in the Earth’s inner core, which is in a solid state.
B. originates in the Earth’s outer core, which is in a liquid state.
C. reverses in polarity once every 300 years or so.
D. results from a bar magnet inside it.
E. [All but one of the above.]
10.) We determined the age of Moon rocks by
A. measurements of radioactive decay products in the rocks.
B. careful examination of the site from which they were acquired.
C. careful chemical analysis of the constituents.
D. counting of the numbers of small craters on the rock surface.
11.) Which of these planets is closest to the Sun?
A. Uranus
B. Earth
C. Venus
D. Mars
E. Mercury
12.) What prompted the 18th-century astronomers to search for a planet between Mars and Jupiter?
A. Gravitational theory
B. Bode’s law
C. Greek legend
D. Satellite theory
E. [Both A and D.]
13.) Which planets revolve around the Sun in the same direction that Earth does?
A. Mercury and Venus only
B. Mercury, Venus, and Mars only
C. Venus, Mars, and Jupiter only
D. All of the planets
E. [None of the above.]
14.) In general, planets of which group are made up mostly of solid material?
A. Jovian
B. Terrestrials
C. [No general statement can be made.]
15.) In general, planets of which group are more massive?
A. Jovian
B. Terrestrials
C. [No general statement can be made.]
16.) In order to find the chemical composition of planetary atmospheres we use
A. the measurement of the masses of these objects.
B. the albedo measurements of the planets.
C. the temperature measurements of the planets.
D. spectroscopy.
1.) D
2.) C
3.) D
4.) A
5.) B
6.) B
7.) C
8.) A
9.) B
10.) A
11.) E
12.) B
13.) D
14.) B
15.) A
16.) D