UniverseTenth Edition

Chapter 7Comparative Planetology I:

Our Solar System

Roger Freedman • Robert Geller • William Kaufmann III

Clicker Questions

Which of the following correctly identifies the characteristics of a terrestrial planet?

A. Dense (> 3000 kg/m3), made mostly of H and He, many rings and moons, no solid surface

B. Less dense (< 3000 kg/m3), made mostly of H and He, many rings and moons, no solid surface

C. Dense (> 3000 kg/m3), contains very little H and He, no rings and few moons, solid surface

D. Dense (> 3000 kg/m3), contains very little H and He, many rings and moons, no solid surface

E. Less dense (< 3000 kg/m3), made mostly of H and He, no rings and few moons, no solid surface

Q7.1

Which of the following correctly identifies the characteristics of a terrestrial planet?

A. Dense (> 3000 kg/m3), made mostly of H and He, many rings and moons, no solid surface

B. Less dense (< 3000 kg/m3), made mostly of H and He, many rings and moons, no solid surface

C. Dense (> 3000 kg/m3), contains very little H and He, no rings and few moons, solid surface

D. Dense (> 3000 kg/m3), contains very little H and He, many rings and moons, no solid surface

E. Less dense (< 3000 kg/m3), made mostly of H and He, no rings and few moons, no solid surface

A7.1

Which of the following correctly identifies the characteristics of a Jovian planet? A. Dense (> 3000 kg/m3), made mostly of H and He,

many rings and moons, no solid surface B. Less dense (< 3000 kg/m3), made mostly of H and

He, many rings and moons, no solid surface C. Dense (> 3000 kg/m3), contains very little H and He,

no rings and few moons, solid surface D. Dense (> 3000 kg/m3), contains very little H and He,

many rings and moons, no solid surface E. Less dense (< 3000 kg/m3), made mostly of H and

He, no rings and few moons, no solid surface

Q7.2

Which of the following correctly identifies the characteristics of a Jovian planet?

A7.2

A. Dense (> 3000 kg/m3), made mostly of H and He, many rings and moons, no solid surface

B. Less dense (< 3000 kg/m3), made mostly of H and He, many rings and moons, no solid surface

C. Dense (> 3000 kg/m3), contains very little H and He, no rings and few moons, solid surface

D. Dense (> 3000 kg/m3), contains very little H and He, many rings and moons, no solid surface

E. Less dense (< 3000 kg/m3), made mostly of H and He, no rings and few moons, no solid surface

What properties of Pluto led to its reclassification as a trans-Neptunian dwarf planet?A. It has a highly eccentric orbit (eccentricity =

0.25). B. It is a very rocky object. C. It is significantly smaller than any other

planet in the solar system. D. Numerous trans-Neptunian objects the size

of Pluto have been discovered.E. All of the above.

Q7.3

What properties of Pluto led to its reclassification as a trans-Neptunian dwarf planet? A. It has a highly eccentric orbit (eccentricity =

0.25). B. It is a very rocky object. C. It is significantly smaller than any other

planet in the solar system. D. Numerous trans-Neptunian objects the size

of Pluto have been discovered.E. All of the above.

A7.3

What is a major difference between asteroids and comets? A. Asteroids contain large amounts of ices, whereas

comets do not. B. Asteroids are mostly located in the outer solar

system, whereas comets are mostly located in the inner solar system.

C. Comets contain large amounts of ices, whereas asteroids do not.

D. Asteroids show long tails when they enter the inner solar system, whereas comets do not.

E. There is no essential physical difference between comets and asteroids.

Q7.4

What is a major difference between asteroids and comets? A. Asteroids contain large amounts of ices, whereas

comets do not. B. Asteroids are mostly located in the outer solar

system, whereas comets are mostly located in the inner solar system.

C. Comets contain large amounts of ices, whereas asteroids do not.

D. Asteroids show long tails when they enter the inner solar system, whereas comets do not.

E. There is no essential physical difference between comets and asteroids.

A7.4

The central peak seen in this crater is the result of

A. plate tectonics.B. a high-speed

impact.C. volcanic activity.D. another meteor

impact.E. either A or C

above.Q7.5

The central peak seen in this crater is the result of

A. plate tectonics.B. a high-speed

impact.C. volcanic activity.D. another meteor

impact.E. either A or C

above.A7.5

If a moon of a planet shows very few craters, we can immediately conclude that

A. the moon is in the shadow of a very large planet.

B. the moon has a very hard surface. C. the moon is geologically active. D. the magnetic field of the moon shields it

from meteors. E. the moon is geologically inactive.

Q7.6

If a moon of a planet shows very few craters, we can immediately conclude that

A. the moon is in the shadow of a very large planet.

B. the moon has a very hard surface. C. the moon is geologically active. D. the magnetic field of the moon shields it

from meteors. E. the moon is geologically inactive.

A7.6

Compared to planet #1, planet #2 has 1/2 the radius, 1/4 the surface area, and only 1/8 the volume of #1. Compared to planet #1, planet #2A. will cool off more rapidly.B. will sustain less geologic

activity.C. will be more heavily

cratered.D. Only A and C are correct.E. A, B, and C are correct.

Q7.7

Compared to planet #1, planet #2 has 1/2 the radius, 1/4 the surface area, and only 1/8 the volume of #1. Compared to planet #1, planet #2A. will cool off more rapidly.B. will sustain less geologic

activity.C. will be more heavily

cratered.D. Only A and C are correct.E. A, B, and C are correct.

A7.7

Mars is more heavily cratered than the Earth. This is because A. for a long time Mars has had little geologic

activity. B. meteors are much more plentiful very close to

the Sun where Earth is located. C. long ago Mars was very hot and its surface

formed blisters. D. Mars is close to Jupiter, and Jupiter’s gravity

causes more meteors to strike Mars than Earth. E. erosion from running water has caused the

Martian craters.Q7.8

Mars is more heavily cratered than the Earth. This is because A. for a long time Mars has had little geologic

activity. B. meteors are much more plentiful very close to

the Sun where Earth is located. C. long ago Mars was very hot and its surface

formed blisters. D. Mars is close to Jupiter, and Jupiter’s gravity

causes more meteors to strike Mars than Earth. E. erosion from running water has caused the

Martian craters.A7.8

The magnetic field of a planet is produced by

A. magnetized iron inside the planet, which mimics a bar magnet.

B. the solar wind captured by the planet. C. electric currents in a solid conducting region inside

the planet. D. electric currents in a liquid conducting region inside

the planet. E. electric currents in a solid non-conducting region

inside the planet.Q7.9

The magnetic field of a planet is produced by

A. magnetized iron inside the planet, which mimics a bar magnet.

B. the solar wind captured by the planet. C. electric currents in a solid conducting region inside

the planet. D. electric currents in a liquid conducting region

inside the planet. E. electric currents in a solid non-conducting region

inside the planet.A7.9

Which substance inside Jupiter carries electric currents that produce a magnetic field?

A. Liquid metallic hydrogen B. Liquid conducting iron C. Solid conducting iron D. Solid metallic hydrogen E. Liquid non-conducting iron

Q7.10

Which substance inside Jupiter carries electric currents that produce a magnetic field?

A. Liquid metallic hydrogen B. Liquid conducting iron C. Solid conducting iron D. Solid metallic hydrogen E. Liquid non-conducting iron

A7.10