Download Quiz # 5

Introductory Astronomy
Fall 2002
Quiz # 5
Name___________________________
1. What name is given to the concentration of mass that formed at the center of the solar
nebula, and eventually became the Sun?
A) The solar hub
B) The antisun
C) The protosun
D) The pseudosun
2.
A)
B)
C)
D)
Accretion is the process by which
elements are transformed into heavier elements by nuclear reactions.
massive protoplanetary cores pull gas onto themselves to create giant planets.
clouds of interstellar gas and dust contract to form protostars.
dust grains and ice crystals coalesce to form planetesimals.
3. The most probable process for the formation or acquisition of the planets of the Sun is
A) capture of planets from outer space by gravity.
B) relatively slow growth of smaller objects by collisions and mutual gravitational
attraction.
C) the freezing of immense gas clouds by the cold temperature of space.
D) the break-up by tidal distortion of one single large companion body to the Sun.
4.
A)
B)
C)
What is a proplyd?
A protoplanetary disk, such as those observed around some stars in the Orion nebula.
Any planet of greater mass than Jupiter.
A planet orbiting a star beyond the Sun; for example, the planet orbiting the star 51
Pegasi.
D) A primitive organism thought to exist on Jupiter's moon, Europa.
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5. The Earth has an average density of 5.5 g/cm3 although the density of rock on its surface
is about 3.0 g/cm3. What conclusion can be reached about the Earth's core from this
observation?
A) It consists of lower density material than surface rock.
B) It must be composed of material with density about the same as that of the surface
material.
C) It must be very hot.
D) It is made of material far denser than surface rock.
Bonus. The temperature of the various planets is determined primarily by
A) atmospheric pressure.
B) distance from the sun.
C) reflectivity of the planet.
D) amount of radioactivity still occurring in the planet.
I pledge that I have neither given nor received any unauthorized aid on this assignment.
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Answer Key
1.
2.
3.
4.
5.
6.
C
D
B
A
D
B
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