Phys 100 – Astronomy (Dr. Ilias Fernini)
Review Questions for Chapter 8
MULTIPLE CHOICE
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2.
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3.
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4.
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5.
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Granulation is caused by
a. sunspots.
b. rising gas below the photosphere.
c. shock waves in the corona.
d. the solar wind flowing away from the corona.
e. the heating in the chromosphere.
In some regions of the corona, the magnetic field does not loop back to the sun, and the gas escapes
unimpeded. These regions are called _________________ and are believed to be the source of the solar wind.
a. prominences
b. flares
c. granules
d. auroras
e. coronal holes
Most of the light we see coming from the sun originates in the
a. chromosphere.
b. photosphere.
c. corona.
d. sunspots.
e. magnetic field.
Modern astronomers suspect the corona is heated by
a. shock waves rising from below the photosphere.
b. the solar wind.
c. the solar magnetic field.
d. all of these
e. none of these
The centers of granules
a. are hot material rising to the photosphere from below.
b. are cool material falling from the photosphere to the regions below.
c. are fainter and hotter than their surroundings.
d. are brighter and cooler than their surroundings.
e. show strong Zeeman effects.
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6.
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7.
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8.
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9.
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The _______ is (are) the hot gases that are the moving extension of the sun's corona.
a. spicules
b. prominences
c. flares
d. supergranules
e. solar wind
__________ occur(s) because photons we receive from the edge of the solar disk are emitted further from the
base of the photosphere than the photons we receive from the center of the solar disk.
a. The Zeeman Effect
b. Sunspots
c. Solar flares
d. Solar prominences
e. Limb darkening
High temperatures are required to get H nuclei to fuse because they ____________ one another because of
their _________________electric charges.
a. attract, negative
b. attract, positive
c. repel, negative
d. repel, positive
Most of the energy emitted by the sun is generated in the
a. corona.
b. photosphere.
c. chromosphere.
d. core.
10. The energy generated by the sun is released by the _________ to make ________nuclei.
* a. fusion of H nuclei, He
b. fusion of He nuclei, H
c. fission of H nuclei, He
d. fission of He nuclei, H
11. Fusion is promoted in the core of the sun by the ____________ there.
a. low temperature and low density
* b. high temperature and high density
c. low temperature and high density
d. high temperature and low density
12. Sunspots are dark because
a. regions of the photosphere are obscured by material in the chromosphere.
b. shock waves move through the photosphere.
c. the sun rotates differentially.
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d.
e.
the strong magnetic field inhibits the currents of hot gas rising from below.
they radiate their energy into space faster than the rest of the photosphere.
13. The intensity of a sunspot is found to be 3 times smaller than the intensity emitted by the solar surface. What
is the approximate temperature of this sunspot if the temperature of the solar surface is 5,800 K?
* a. 4,400 K
b. 470,000 K
c. 1,900 K
d. 7,600 K
e. 1,400 K
14. The solar constant is a measure of
* a. the amount of solar energy reaching the earth.
b. the length of the sunspot cycle.
c. the period of rotation of the sun's equator.
d. the average number of sunspots seen during the Maunder minimum.
e. the sun's mass.
15. The sunspot cycle affects
I.
the latitude at which sunspots are visible at a given time.
II. the number of sunspots that are visible at a given time.
III. the rotation rate of the sun's equator at a given time.
IV. the magnetic polarity of the sunspots at a given time.
*
a.
b.
c.
d.
e.
I & II
I & IV
II & III
I, II & III
I, II, & IV
16. The sun's magnetic field is evident in the looped shapes of
a. solar flares.
b. sunspots.
c. the corona.
d. granules.
* e. solar prominences.
17. Spicules
a. are found in the photosphere.
b. are magnetic disturbances that push large loops of material off the solar surface.
c. are responsible for twisting the solar magnetic field and causing the sunspot cycle.
d. appear in the corona near the north and south poles of the sun during a total solar eclipse.
* e. are visible in filtergrams of the solar chromosphere.
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18. The most recent sunspot maximum occurred in 2001. When is the next sunspot maximum expected if the
solar cycle continues?
a. 1990
b. 2006
* c. 2012
d. 2023
e. The last cycle started a Maunder minimum, and the next maximum can not be predicted.
19. A ___________ is believed to occur when energy, stored in a twist in the solar magnetic field above a sunspot,
is suddenly released.
* a. solar flare
b. supergranule
c. spicule
d. coronal hole
e. none of the above
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20. The United States consumes 2.510 J of energy each year. A typical solar flare releases 5.010 J of energy.
How many years could we run the United States on the energy released by this solar flare if all of the released
energy could be used?
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a. 510 years
* b. 200,000 years
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c. 1.2510 years
d. about 12 years
e. 500 years
21. What is the explanation for the pattern of granulation seen on the visible surface of the Sun?
a. The granules form the base of a circulation pattern that extends from the photosphere to the outer corona.
b. The granules are regions of nuclear energy generation in the Sun's photosphere.
c. Each granule contains a strong magnetic field, which compresses and heats the gas underneath it.
* d. The granules are the tops of hot gas that have risen from the Sun's convective zone.
22. The gas motions within granules on the solar surface are
a. upward in the centers of some cells and downward in others; the gas cools as it passes between individual
granules.
b. actually motionless. The dark regions are absorption features from gases in the photosphere.
* c. upward in the bright cell centers and downward around the darker edges.
d. downward in the bright cell centers and upward around the darker edges.
23. What are the three layers of the Sun's atmosphere, in order of increasing distance from the surface?
a. Corona, chromosphere, photosphere
b. Photosphere, corona, chromosphere
* c. Photosphere, chromosphere, corona
d. Chromosphere, photosphere, corona
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24. The rotation of the Sun is
* a. fastest at the equator, slower at mid-latitudes, and slowest near the poles.
b. slowest at the equator, faster at mid-latitudes, and fastest near the poles.
c. fastest at the equator, slowest at mid-latitudes and the poles which travel at the same speed .
d. the same regardless of latitude.
25. Why is the temperature at the region of a sunspot cooler than the photosphere?
a. They are holes in the photosphere that reveal the lower temperature gases in the deeper layers.
b. They represent points where streams of cool gas from the corona lower the temperature in those regions
of the photosphere
c. Powerful magnetic fields in the sunspots act upon the atoms of the photosphere to prevent them from
emitting light.
* d. Powerful magnetic fields inhibit the convective flow of the gases of the photosphere allowing them to
cool for longer than would normally be permitted.
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