Download Phys 100 – Astronomy (Dr. Ilias Fernini) Review Questions for

Phys 100 – Astronomy (Dr. Ilias Fernini)
Review Questions for Chapter 6
MULTIPLE CHOICE
1.
*
The nebular theory of the origin of the solar system was proposed by
a. Laplace.
b. Buffon.
c. neither of these
2.
The passing star mechanism of the origin of the solar system was proposed by
a. Descartes.
b. Laplace.
c. Buffon.
d. none of the above
*
3.
*
Which of the following observations would support the solar nebula theory over the passing star hypothesis?
a. proving that most of the solar like stars near the sun also have planets orbiting them.
b. proving that none of the stars near the sun has planets orbiting them
c. finding a planet located beyond the orbit of Pluto
d. finding a meteorite whose age proved to be greater than 4.6 billion years
e. proving that Mercury has the same uncompressed density as Earth
4.
Which one supports the solar nebula theory of the origin of the solar system?
a. Planets are round.
b. The sun is the least massive object in the solar system.
c. Disks are common around young stars.
d. Disks are rare around young stars.
*
5.
*
The oldest rocks found on Earth are about ____________ years old.
a. 10 billion
b. 5.3 billion
c. 4.6 billion
d. 3.9 billion
e. 6.2 million
6.
*
Which of the following is not a characteristic of the terrestrial planets?
a. low average density
b. orbits inside the asteroids
c. craters in old surfaces
d. small diameters
e. very few satellites
7.
A(n) __________ is a solar system object that enters Earth's atmosphere and becomes very hot due to friction
between the object and Earth's atmosphere.
a. asteroid
b. meteor
c. comet
d. meteoroid
*
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8.
*
9.
*
e. planetesimal
The age of the solar system is believed to be approximately 4.6 billions years old based on the data from
a. samples of lunar rocks.
b. samples of earth rocks.
c. samples of meteorites.
d. all of the above
e. none of the above
In observations, _______has a heavy element core, and a deep atmosphere made mostly of hydrogen.
a. Uranus
b. Mars
c. Venus
d. an asteroid
e. a meteor
10.. The current atmosphere of Earth is believed to be
a. the remnants of the original gas from the solar nebula attracted by the protoplanet.
b. the result of the melting and vaporizing of the glaciers from the last ice age.
c. composed primarily of hydrogen and helium.
* d. composed of gases that were baked from the rocks sometime after the planet formed.
e. the result of a collision between the sun and another star.
11. The most important effect in clearing the solar nebula of gas and dust was
a. impacts by planetesimals.
b. the solar wind.
c. the sun's magnetic field.
d. the asteroid belt.
* e. radiation pressure.
12. On a photograph of the moon, the moon measures 30 cm in diameter, and a small crater measures 0.2 cm.
The moon's physical diameter is 1738 km. What is the physical diameter of the small crater?
a. about 1738 km
* b. about 12 km
c. about 520 km
d. about 350 km
e. 3.5 km
13. The speed of the solar wind is approximately 400 km/s and the distance from the sun to Saturn is 9.5 AU (1 AU
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= 1.510 km). How long does it take a particle in the solar wind to reach Saturn?
a. about 4.1 hours
b. about 4.1 days
* c. about 41 days
d. about 4.1 years
e. about 41 years
14. Once a terrestrial planet had formed from a large number of planetesimals, heat from ____________ could
have melted it and allowed it to differentiate into a dense metallic core and a lower density crust.
* a. radioactive decay
b. the sun
c. volcanic eruptions
d. tidal forces
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e. impacts of small meteorites
15. Nearly all extra-solar planets actually found thus far are
a. less massive than earth.
b. equal to earth’s mass.
* c. much more massive than earth.
16. A future news release might report that a new planet has been found around a star very similar to our sun.
This newly discovered planet is claimed to have a mass 40 times that of Earth and is located nearly 25 AU from
the star it orbits. Which of the following would be a reasonable prediction about this planet?
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I. The planet will probably have a mean density of around 5 g/cm .
II. The planet will probably have a radius of around five to ten times greater than Earth's.
III. The planet will probably have several satellites.
IV. The planet will probably have a composition that is mostly hydrogen and helium.
*
a.
b.
c.
d.
e.
I and IV
I, II, & III
II, III, & IV
I, II, & IV
I, II, III, & IV
17. Most planets thus far discovered around other stars were found by
a. seeing the planet next to the star.
b. traveling to the star.
* c. varying Doppler shifts of the stars.
d. The planet blotting out the light of the star.
18. Planets are thought to be forming today in ______around stars.
* a. hot disks
b. cold disks
c. spherical clouds
d. none of the above
19. What observation made of other stars seems to suggest the solar nebula hypothesis is correct?
a. Stars are found to exist more often in binaries than by themselves.
b. Protostars are seen to radiate much of their light at infrared wavelengths.
c. Nearby stars tend to be low mass red dwarfs.
* d. Young stars are found to have hot disks that surround them.
20. Venus is often called Earth’s sister planet because it is similar to the Earth in terms of
a. mass.
b. size
c. density
* d. All of the above.
21. Compared to the terrestrial planets, Jovian planets
a. have a higher density.
b. have a smaller number of moons.
* c. have a much larger diameter.
d. are much hotter.
22. The asteroid belt is found between which two planets?
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*
a.
b.
c.
d.
Earth and Mars
Mars and Jupiter
Jupiter and Saturn
Venus and Earth
23. If the catastrophic theory of the formation of the solar system is correct then we should expect
a. to find many planetary systems like our own.
* b. to find a very few number of planetary systems like our own.
c. to find no other planetary system anywhere in the universe.
d. Misleading; the catastrophic theory is not a theory of planetary formation.
24. How is radioactive dating used to determine the age of an object?
* a. The amounts of radioactive and decay material are compared to its half-life to determine age.
b. The rate of radioactive decay is measured and compared to models.
c. The amount of decay product weighted to determine age.
d. The amount of heat generated by radioactive dating is measured to determine age.
25. How is the presence of space debris accounted for by solar system models?
a. Space debris is left over material from the early solar system that never formed into a planet.
b. Space debris was formed by the collision of objects after the planets formed.
c. Space debris is material that existed in our region of space before the sun formed.
* d.. Both a and b.
e. All of the above.
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