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NAME: _____________________________________________
ASTR 103 – Astronomy, Section B01
Summer 2000
Mid-Term Exam
26 June 2000
Instructions: For matching questions, write the letter of the best answer on the blank line next to the number of the problem. For
multiple choice questions, simply circle the letter of the one best answer. For short answer questions, write the correct answer in the
blank space provided. Each of the multiple choice, matching, and short answer questions is worth 1 point. For the essay questions
write your essays in the test booklet. Essay questions are worth 10 points (the last one is worth 20 points!). The combined total of all
questions is 100 points.
Definitions: Match the given word with the correct definition from the list of definitions that are lettered a through e.
1. ___ Celestial poles
2. ___ Zodiac
3. ___ Precession
4. ___ Celestial sphere
5. ___ Constellations
a. Imaginary dome centered on the Earth to which the Sun, Moon, planets, and stars appear
to be affixed.
b. The regions with definite east-west and north-south boundaries which cover the whole
sky.
c. Positions in the sky determined by the axis of rotation of the Earth.
d. The star patterns along the ecliptic as seen from the orbital motion of the Earth around
the sun.
e. The motion of Earth’s axis of rotation about a perpendicular to Earth’s orbital plane.
6.
The seasons on Earth are caused by
a. the Sun being closer to the Earth at certain times of the year.
b. the tilt of the plane of the Moon's orbit to the plane of the Earth's orbit.
c. the inclination of the rotation axis of the Earth to the ecliptic.
d. the motion of the vernal equinox along the equator.
7.
Science is based fundamentally on the belief that the universe is comprehensible. In addition, a good scientific theory MUST
a. make testable predictions.
b. satisfy aesthetic desires.
c. conform to established preconceptions.
d. none of the above.
8.
If the nearest star is 4.2 light years from the Solar System, then
a. the light we see left the star 4.2 years ago.
b. the star must be in another galaxy.
c. the star is 4.2 million AU from us.
d. the star must have formed 4.2 billion years ago.
Definitions: Match the given word with the correct definition from the list of definitions that are lettered a through e.
9. ___ Total solar eclipse
a. Occurs when the Earth is covered by Moon’s full shadow.
10. ___ Partial solar eclipse
b. Occurs when the Earth is covered by Moon’s semidark shadow.
11. ___ Annular solar eclipse
12. ___ Synodic
c. Occurs when the Moon is farthest from Earth and the Moon’s umbra is too short to reach
Earth.
d Synchronized motion relative to the distant fixed stars.
13. ___ Sidereal
e. Synchronized motion relative to the Sun’s position in the sky.
14. Which period of time is NOT based on a naturally occurring cyclical period of objects in the sky?
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NAME: _____________________________________________
a.
b.
c.
d.
Day
Week
Month
Year
15. Which of the following is TRUE?
a. Solar days are 24 hours and 4 minutes.
b. Sidereal days are approximately 23 hours and 56 minutes.
c. Solar days are based on the apparent rotation period of the celestial sphere.
d. Sidereal days are based on the apparent rotation period of the sun.
e. Sidereal days are longer than solar days.
16. The are two ocean tides each day and they are cause by
a. gravity locking of the Moon’s orbital period with its rotation period.
b. the Moon’s gravity pulling the oceans first towards the moon during the day and away from the moon during the night.
c. the Earth rotating through the world’s oceans which have been made oblate by the tidal forces of the Moon’s gravity.
d. the Moon’s gravity for high tides and the Sun’s gravity for low tides.
Definitions: Match the given word with the correct definition from the list of definitions that are lettered a through e.
17. ___ Archeastronomy
18. ___ Retrograde motion
19. ___ Geocentric
a. Apparent change in position of a nearby object when viewed against distant background
objects.
b. Tells us that ancient cultures used the motions of the heavens as clocks and calendars.
20. ___ Heliocentric
c. Apparent reversal of direction of the planet's motion relative to the background stars
when observed during the Earth’s annual motion.
d. Centered on the Earth.
21. ___ Parallax
e. Centered on the sun.
22. Copernicus’ model for the planetary system
a. had the Earth at the center of the Solar System and the planets moving along epicycles.
b. placed the Sun at the center of the Solar System, but retained the idea of epicycles and deferents.
c. retained the Earth at the center of the Solar System, but eliminated epicycles.
d. none of the above.
23. Copernicus is famous for leading a revolution in human thought about the universe; the title of his famous work was the
a. Almagest.
b. Sidereal Messenger.
c. Mystery of the Universe.
d. Principia.
e. The Revolution of the Heavenly Orbs.
24. Galileo was the first person to use this instrument for astronomical observations?
a. Abacus.
b. Sextant.
c. Telescope.
d. Compass.
25. Kepler's second law says that planets in their elliptical orbits
a. have the Sun at one focus and the planet at the other focus.
b. have periods that are equal to their semi-major axis.
c. sweep out equal areas in equal times.
d. every action has an equal and opposite reaction.
Definitions: Match the given word with the correct definition from the list of definitions that are lettered a through e.
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NAME: _____________________________________________
27. ___ Gravitational force
a. Quantitative measure of the inertia or resistance a body offers to a change in its state of
motion. As in F=ma and F=GMm/r2 .
b. A body at rest tends to stay at rest, and a body in motion tends to stay in motion.
28. ___ Newton’s 1st Law
c. The time-rate of change of velocity or direction of motion a body at any instant of time.
29. ___ Acceleration
d. The attraction that all massive bodies have for each other.
30. ___ Weight
e. A measure of the gravitational force of a body on the surface of a planet or moon. On the
Earth it is 6 time stronger than on the moon and 3 times stronger than on Mars.
26. ___ Mass
31. Galileo’s telescopic observations of the moons of which planet demonstrated that gravitation allowed for “mini solar systems”?
a. Venus.
b. Earth.
c. Mars.
d. Jupiter.
32. According to Newton’s second law of motion, a force must be acting whenever
a. an object’s mass changes.
b. an object moves with constant speed.
c. time passes.
d. an object’s state of motion changes, i.e. it accelerates.
e. none of the above.
33. Einstein’s theory of gravity replaced Newton’s as a more accurate description of gravitational phenomenon. Which of the
following would be an apt description of Einstein’s theory of gravity?
a. Gravity as curvature of space-time.
b. Action at a distance.
c. Quantum Gravity.
d. A pound of feathers falls at the same rate as a pound of lead.
Definitions: Match the given word with the correct definition from the list of definitions that are lettered a through e.
34. ___ Reflector
35. ___ Refractor
36. ___ Light gathering power
a. Generally, the least important characteristic of a telescope.
b. Ability of a telescope to discern detailed features in an image. Improves for larger
objectives.
c. Proportional to the area of the objective.
37. ___ Resolving power
d. Telescope made with a transparent lens as the objective.
38. ___ Magnification
e. Telescope made with a silver or aluminum coated surface as the objective.
39. Outside the Earth's atmosphere, the scintillation (twinkling) of stars
a. is far more pronounced than from Earth's surface.
b. is about the same as from Earth's surface.
c. is slightly less pronounced than from Earth's surface.
d. does not happen.
40. The two ranges of electromagnetic radiation for which the Earth’s atmosphere is reasonably transparent are
a. visible and far infrared radiation.
b. X-rays and visible radiation.
c. UV and radio waves.
d. visible and radio waves.
41. Which is the correct ordering of the electromagnetic spectrum from long to short wavelength?
a. Radio, microwaves, infrared, visible, ultraviolet, x-rays, gamma rays.
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NAME: _____________________________________________
b.
c.
d.
Visible, ultraviolet, infrared, x-rays, microwaves, gamma rays, radio.
Gamma rays, x-rays, ultraviolet, visible, infrared, microwaves, radio.
Ultraviolet, gamma ray, visible, x-ray, radio, infrared, microwave.
Definitions: Match the given word with the correct definition from the list of definitions that are lettered a through e.
42. ___ Planck’s Law
a. Mathematical law describing distribution of brightness in blackbody spectrum: it goes to
zero at the ends and has a peak somewhere in the middle of the spectrum
43. ___ Stefan-Boltzmann
Law
b. Continuous spectrum with energy emitted at all wavelengths according to Planck’s law,
Stefan-Boltzmann law, and Wien’s displacement law. For example, a red-hot cast iron
skillet.
c. Maximum emission found toward shorter wavelengths (blue end of spectrum) as
temperature increases—i.e., the peak frequency is displaced towards shorter wavelengths.
d. Radiation given off at only certain frequencies based on the difference in energy levels of
atoms. From the quantum theory atoms and electromagnetic radiation.
e. Total amount of radiant energy emitted increases with increasing temperature raised to
the fourth power.
44. ___ Wien’s displacement
Law
45. ___ Blackbody Radiation
46. ___ Line emission
47. For a star moving away from the Solar System, the absorption and emission lines of the electromagnetic radiation spectrum will be
Doppler shifted, that is
a. reversed so that red wavelengths will become blue and blue wavelengths will become red ones.
b. blueshifted, that is, shifted toward shorter wavelengths.
c. unaffected.
d. redshifted, that is, shifted toward longer wavelengths.
48. The process of removing an electron from an atom is known as
a. ionization.
b. Doppler effect.
c. random thermal collision.
d. a redshift.
e. none of the above.
49. A common feature in the absorption spectra of starlight, and with frequencies in the visible light range, is the ___________ of the
hydrogen atom
a. Balmer series
b. Lyman series
c. Paschen series
d. K lines
e. None of the above
Definitions: Match the given word with the correct definition from the list of definitions that are lettered a through e.
50. ___ Venus
51. ___ Mars
52. ___ Jupiter
53. ___ Uranus
54. ___ Pluto
a. Run-away greenhouse effect; carbon dioxide atmosphere.
b. May also be called a trans-neptunian object; nitrogen methane atmosphere; not always
the furthest planet from the Sun.
c. First new planet discovered (by Herschel) since ancient times; hydrogen water and lots of
chemicals.
d. ¾ of all planetary mass; mostly hydrogen; great red spot is a giant hurricane-like storm
lasting for centuries.
e. Probably had water in the past, but now has dust storms; thin atmosphere is 1% as dense
as the Earth’s. Was “in the news last week!”
55. The favored scientific opinion on the origin of the solar system is that it formed from
a. a coalescing debris cloud created by the gravitation pull of a star passing too near the sun.
b. the collapse of a gas and dust nebula in our region of the galaxy.
c. a catastrophic collision of a binary star system.
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NAME: _____________________________________________
d.
the sun’s rotation increasing until parts of its outer atmosphere were thrown off to form planetesimals.
56. The planets formed into two main groups: the inner terrestrial planets and the outer Jovian planets. Which of the following is
NOT characteristic of the formation sequence of the terrestrial planets?
a. Heavy elements condense to form grains and then planetesimals.
b. Planetesimals coalesce and then form planetary cores.
c. The Sun’s radiation pushes gas to the outer solar system.
d. Planet cores sweep up huge volumes of gas.
e. Remaining planetesimals are accreted by the sun and planets leaving impact craters.
57. Comets are believed to originate in
a. primordial debris from the Jovian system ejected by Jupiter’s moons.
b. the asteroid belt.
c. neighboring stars systems.
d. the Kuiper Belt and the Oort cloud at the outer edge of our solar system.
58. We expect that the existence of planets around other star is likely since
a. they exist around the sun, they may exist elsewhere.
b. we observe Doppler shifted spectra from nearby stars indicating they have a Jupiter-sized planet in orbit around them.
c. we observe infrared images showing large, dust disks around nearby stars.
d. all of the above.
59. Which of the Moons of Jupiter is characterized by an exceptionally smooth, icy surface, few craters, and many streaks and cracks?
a. Io
b. Europa
c. Callisto
d. Ganymede
60. What is the source of Jupiter's intense magnetic field?
a. Electric currents in Jupiter's liquid hydrogen mantle.
b. Electric currents in Jupiter's molten rocky core.
c. A permanently magnetized iron core.
d. Electric currents in ionized layers of Jupiter's atmosphere.
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NAME: _____________________________________________
Essay Question. Choose ONE of the following two questions and write a short essay in the test booklet below. Be concise, but use
enough detail, terminology, and quantitative information to provide thorough answer. Draw figures where appropriate. A one page
answer should suffice, but you can use the backside of the page if more space is needed but a second page is provided if necessary.
(10 points)
E1. Describe the basic function of a telescope. What are the basic types, how do they compare, and how do we
characterize telescope performance?
or
E2. Suppose you look up at the night sky and observe some of the brightest stars with your naked eye. Is there any way
of telling which stars are hot and which are cool? Also, is there anyway to tell if they are moving towards us or away from
us?
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NAME: _____________________________________________
Essay Question. Choose ONE of the following two questions and write a short essay in the test booklet below. Be concise, but use
enough detail, terminology, and quantitative information to provide thorough answer. Draw figures where appropriate. A one page
answer should suffice, but you can use the backside of the page if more space is needed but a second page is provided if necessary.
(10 points)
E3. Describe the planet Jupiter, it’s cloud tops, interior layers, magnetic fields and moons.
or
E4. Discuss the existence of life on Mars, in the past and at the present time.
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NAME: _____________________________________________
Essay Question. This one is mandatory. Write a short essay in the test booklet below. Be concise, but use enough detail,
terminology, and quantitative information to provide thorough answer. Draw figures where appropriate. You will probably need to use
the front and backside of the answer sheet for a thorough essay. (20 points)
E5. Describe the formation of the solar system; specifically address how this led to the formation of the inner terrestrial
planets, the outer gas giant planets, the Earth, the Earth’s mantel and core, and the moon.
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