Download PTYS/ASTR 206 – Section 2 – Spring 2006 Practice Exam 1 Note

PTYS/ASTR 206 – Section 2 – Spring 2006 Practice Exam 1
Note: The exam is scheduled for Thursday, February 15, 2006. It will be held in-class; you will
have 70 minutes to finish the exam, though many of you will most likely not need the entire
allotted time to complete the exam. Please remember to bring a #2 pencil to fill out the scantron
sheet.
Please note that this practice exam is meant to serve as an additional study source – the exam on
Thursday is not going to have the same questions!! Be sure to study your notes, the instructor
lecture slides, the activities, homework, and textbook in addition to this practice exam.
The format of the exam will be 30 multiple-choice questions and 5 short-answer/essay questions.
All material covered in class and in the textbooks up to Tuesday, February 13th are fair game.
Part I -Multiple Choice
1. During which phase of the Moon can an annular solar eclipse occur?
A. New
B. Full
C. Crescent
D. Gibbous
2. Which best describes the Earth's orbit around the Sun?
A. a perfect circle
B. an ellipse with a small eccentricity ( e < 0.1)
C. an ellipse with a large eccentricity ( e > 0.1)
D. parabolic
3. The spectrum of a hot, transparent gas shows
A. bright (emission) lines
B. a continuous spectrum
C. dark (absorption) lines
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4. Newton’s Law of Universal gravitation is F=Gm1m2/r . You're standing on a planet that is 8
times the mass of the Earth, with a radius 4 times that of Earth's radius. How much would you
weigh on this planet compared to your weight on Earth?
A. your weight would be ¼ of your Earth weight
B. your weight would be ½ of your Earth weight
C. your weight would be the same
D. your weight would be twice your Earth weight
E. your weight would be 4x your Earth weight
5. Compared with visible light, gamma rays
A. are like sound waves
B. are lower frequency
C. travel slower than the speed of light
D. are shorter wavelength
6. At what part of the electromagnetic spectrum is the Sun's radiated energy a maximum?
A. X-rays
B. Ultraviolet
C. Visible
D. Infrared
7. When does the last-quarter moon rise?
A. sunrise
B. sunset
C. noon
D. midnight
8. How old is the solar system?
A. 4.5 million years old
B. 450 million years old
C. 4.5 billion years old
D. 4.5 trillion years old
9. Wien's Law states that the dominant wavelength in which a blackbody radiates is
A. inversely proportional to temperature (higher temp, shorter wavelength)
B. directly proportional to temperature (higher temp, longer wavelength)
C. independent of temperature, depends on the blackbody's mass
D. independent of temperature, depends on the blackbody's composition
10. Which of the following can be attributed to the precession of Earth’s rotational axis?
I. the Earth's seasons
II. Vega will be the “pole star” in ~14,000 years
III. The vernal equinox is slowly shifting towards Aquarius
IV. Polaris currently traces out a small circle over the course of a day
A. I and II only
C. II, III, and IV only
E. none of the above
B. II and III only
D. I, II, III, and IV
11. Which of the following puts the different types of electromagnetic radiation in order of
increasing wavelength?
A. ultraviolet, infrared, X-ray
B. visible, ultraviolet, X-ray
C. X-ray, infrared, ultraviolet
D. X-ray, ultraviolet, visible
12. You're working with a radioactive sample that originally has a mass of 48 grams. The sample
has a half-life of 20 minutes. How long will it take so that only 6 grams of the radioactive sample
remain?
A. 20 minutes
B. 40 minutes
C. 60 minutes
D. 80 minutes
13. The most intense light being emitted by the blackboard is in what part of the electromagnetic spectrum?
A)
B)
C)
D)
black is an absence of color, so it is producing no wavelengths
visible
infrared
radio
14. What other planet, besides Venus, can exhibit a crescent phase as seen from Earth?
A) Mercury
B) Jupiter
C) Mars
D) Europa
15. Which of the following planets would have seasonal weather patterns just like the Earth?
A. Venus, whose average distance from the Sun is the most similar to Earth's.
B. Mars, whose axis is tilted almost the same amount as Earth's
C. Mercury, whose distance to the Sun varies by nearly 50% during one orbit around the
Sun.
nd
16. According to Kepler's 2 Law, when does a planet move slowest?
A. when it is closest to the Sun
B. when its moons are perfectly aligned in a straight line, causing massive tides
C. when it is farthest from the Sun
D. Planets travel at the same speed at all points along its orbit.
17. What object contains a large fraction of the Solar System's mass?
A. the Sun
B. Jupiter
C. Earth
D. the Kuiper Belt
18. How can you increase the magnification of a telescope?
A. Decrease the focal length of the eyepiece.
B. Increase the focal length of the eyepiece.
C. You cannot change a telescope's magnification.
19. What fundamental property of a planet will determine its likelihood of having active
volcanoes (geologic activity)?
A. its distance from the Sun
B. its eccentricity
C. its size
D. the number of moons orbiting around it
20. Why do the planets orbit the Sun in the same direction?
A. the Sun captured the planets from a passing star, so the rotation direction is just a
consequence of the passing star's trajectory
B. the disk of gas and dust from which the planets formed was rotating that way
C. the Sun, from which the planets were ejected out of, was rotating that way
D. it's just a purely random coincidence
21. Which part of the Sun has the lowest temperature?
A. the core
B. the radiative zone
C. the convective zone
D. the photosphere
E. the corona
22. Jupiter is about 5 AU from the Sun. The intensity of the sunlight seen from Jupiter is
A. about the same as seen from Earth
B. about 5 times dimmer than that seen from Earth
C. about 10 times dimmer than that seen from Earth
D. about 25 times dimmer than that seen from Earth.
23. Compared with the terrestrial planets, the Jovian planets
I. are higher in density because of their size
II. are larger
III. have orbits that are beyond those of the terrestrial planets (i.e. further away)
A. Ionly
C. II only
E. I, II, and III
B.I and II only
D. II and III only
24. A star that is directly overhead is
A. at the zenith
B. at opposition
C. the pole star
D. at greatest elongation
25. Epicycles
A. accurately explain the retrograde motion of Mars
B. cause the Earth's seasons
C. accurately model how the phases of Venus change
D. are an artificial construct invented by Ptolemy
26. When Venus is at the crescent phase, its apparent angular size will be
A. at its largest
B. at its smallest
C. Venus's angular size remains constant.
27. What can the lines in a spectrum primarily reveal about a solar system object?
A. its temperature
B. its size
C. its composition
D. its velocity
28. As the Solar System was forming, which of the following best describes the formation of the
terrestrial planets?
A. The Sun was quite energetic and explosive when it first formed. It threw out massive
chunks of solid material, which later cooled off to form the terrestrial planets.
B. The terrestrial planets were randomly captured by the Sun with assistance from Jupiter
– it is not known how they were formed.
C. Gas pockets formed around the Sun. When the Sun ignited, the gas was blown off,
revealing the rocky planets inside.
D. Bits of dust started accreting to form bits of rock. These bits of rock combined with other
bits to form even bigger chunks, and eventually led to a planet-sized object.
29. Astronauts are “weightless” when they orbit the Earth because
A. they are in free-fall, so that everything around them is falling at the same rate they are
B. there's no gravity due to the Earth at the altitude in which they orbit
C. they are at a point in space where the gravity from the Earth, Moon, and Sun perfectly
balance each other
st
30. Newton's 1 Law of Motion states that a body already in motion with no outside forces
acting upon it
A. tends to travel in a circular path
B. tends to travel in an elliptical path
C. tends to travel in a straight line
D. will slow down and eventually stop
The next page has some short answer practice questions
Part II – Short Answer
1
Explain why it is that the planets all orbit the Sun in the same direction.
2
What were the key observations that led scientists to think that the Sun-centered model was
the correct one for the solar system, rather than the Earth-centered model?
3
What happens to the brightness and color of a blackbody as its temperature decreases?
4
Explain retrograde motion of a planet and the fundamental reason(s) why this phenomenon
occurs.
5
Callisto, one of Jupiter’s moons, is the most heavily cratered body in the solar system;
whereas, Io, another of Jupiter’s moons, has no craters at all. What does this tell you about the two
worlds?
****Spoiler Alert! The next page contains the answers to the multiple choice section. Don't peek if
you want to practice the exam questions!***
Answers to multiple choice part:
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