WSU ASTR 135 Exam 1
2-11-2000
1. A light-second can be defined as
a. the distance that light travels during the time that Earth revolves around Sun once
b. the time between Sun and the nearest star
c. the distance that Earth travels in one year as it orbits Sun once
d. the distance light travels in one second
2. 109
a. is the number of miles in a light-year.
b. represents the number 1,000,000,000.
c. is the approximate number of stars in the universe.
d. is one-hundred thousand billion.
3. While expressing the distances to the planets, astronomers would most prefer to use the unit of measurement of
a. miles
b. astronomical units
c. light-years
d. kilometers
4. The apparent visual magnitude scale refers to
a. the visual diameter of stars and planets
b. the diameter of stars that are visible only with the naked eye
c. the apparent brightness of an object
d. how big an object is without correcting for its distance
5. At the largest scale observed by astronomers, superclusters of galaxies appear to be distributed
a. in a pattern of filaments that enclose empty voids.
b. in the Local Group.
c. along straight lines.
d. entirely at random, with no clear organization or pattern.
6. Precession:
a. causes the Earth's rotation to slow down
b. is the wobbling of the Earth's 23 1/2-degree tilted rotation axis
c. causes the north celestial pole to remain always fixed with respect to the North Star Polaris
d. causes precession
7. The modern constellations
a. are asterisms
b. allow historians to recall and/or identify the ancient gods and goddesses
c. are 88 regions of the sky
d. allow astrologers to predict the future
8. What is parallax?
a. A geometric method of measuring distances to objects.
b. An ancient Greek method of describing the planets orbits around the Earth.
c. It is an ancient method of finding distances, no longer useful today.
d. It is a method of measuring the length of small objects, such as pencils.
9. Which of the following is the dimmest on the magnitude scale?
a. -4.3
b. -1
c. 0
d. 15
e. 22
10. The angular distance between the horizon and the north celestial pole
a. depends upon the time of the year.
b. is equal to the observer's latitude.
c. is about two full moon diameters.
d. is zero. They are one and the same.
11. Our system of expressing direction on Earth (i.e., N, S, E, W) is based on
a. the star Vega
b. Earth's rotation
c. the axial tilt of Earth
d. the zenith
12. Why is it harder to observe a total solar eclipse than a total lunar eclipse?
a. Because solar eclipses always occur at the inconvenient time of 3am.
b. A total solar eclipse always occurs during the nighttime.
c. One-half of the Earth's surface is presented with a total solar eclipse, whereas only a small the portion of the Earth's surface is presented with a total lunar eclipse.
d. Only a narrow strip of the Earths surface will see the total solar eclipse.
13. If you observe the sky for several hours during a particular night from Pullman, you will observe
a. the star Polaris remaining stationary at your zenith
b. the apparent motion of stars moving from east to west
c. the constellations changing shape as the stars move relative to one another
d. the stars appear to revolve around the zenith
14. The ecliptic is
a. the center line of the zodiac.
b. the projection of Earth's orbit on the sky.
c. the apparent path of the sun around the sky.
d. all of the above
e. none of these
15. The fact that there are two different time intervals (synodic and sidereal) during which the Moon revolves around Earth is a consequence of the fact that
a. Earth revolves around Sun as Moon revolves around Earth
b. Moon does not orbit Earth in a perfectly circular path
c. Moon's axis of rotation is tilted with respect to its orbital plane around Earth
d. Moon does not orbit exactly along the ecliptic.
e. It alternates from below to above the ecliptic
16. The new Moon is at a node and at apogee.
a. People along a narrow path on the daytime side of Earth are witnessing an annular solar eclipse
b. Moon will rise at midnight for a given observer
c. People on the nighttime side of Earth are witnessing a total lunar eclipse
d. Neap tides are occurring somewhere on Earth
17. The ________ is the point on the celestial sphere directly above any observer.
a. north celestial pole
b. south celestial pole
c. zenith
d. celestial equator
e. asterism
18. What happens on or about March 21st of each year?
a. The summer solstice
b. Sun crosses the ecliptic
c. Earth is most distant from Sun
d. Earth is closest to Sun
19. The date is June 21st, Moon is at 1st Quarter, and you are vacationing at the North Pole:
a. Spring tides are occurring
b. Sun is located directly on your horizon
c. the star Polaris is located 23-1/2 degrees above the horizon
d. Sun is at its greatest distance north of the celestial equator
20. The ecliptic and celestial equator do not coincide, but cross one another at an angle. A consequence of this is that
a. Earth and Moon are slowly separating from one another
b. Earth is not always closest to Sun at the same time of the year
c. The Earths rotation is slowing down
d. Earth experiences seasons
21. For mapping purposes, the Earth is divided into two equal halves by an imaginary line called the equator. Likewise, the sky is divided into two equal halves by an imaginary line called the
a. celestial equator
b. ecliptic
c. line of nodes
d. none of the above. Neither are divided equally
22. New Moon:
a. always occurs twice a given calendar month
b. associated with neap tides
c. Rises at sunrise
d. Rises at sunset
23. If the Moon orbited the Earth exactly along the ecliptic.
a. Ocean tides would not occur
b. Days and nights would no longer be equal on the dates of the equinoxes
c. A total lunar and a total solar eclipse would occur every month
d. Precession would not occur
24. As Moon revolves around Earth once, it rotates
a. once
b. about 29 times
c. 24 times
d. none of the above. Moon does not rotate
25. Which one of the following assumptions do astronomers use as they attempt to explain the universe?
a. Scientific laws are the same throughout the universe
b. Orbital motion is always circular
c. The force of gravity is caused by objects rotating
d. An object can exhibit a change in motion without a force being applied to it
26. The Copernican model of the universe:
a. Describes the orbits of the planets as ellipses.
b. Is the basis for modern astrology.
c. Explained the motions of planets, including retrograde motion, using epicycles.
d. Places the Sun at the center of the universe.
27. One of Galileo's discoveries that played a role in destroying support for the geocentric theory was his discovery that
a. Jupiter has four satellites (moons) orbiting it
b. the idea of planets moving in perfect circles was false
c. the planet Venus goes retrograde
d. gold could be tarnished and changed into other metals
28. The Ptolemaic system accepted by the Church at the time of Galileo could not explain
a. Galileo's discovery of parallax
b. Galileo's observation of the phases of the planet Venus
c. the retrograde motions of the planets
d. the lunar phases
29. What was one of the contributions made by Newton to astronomy?
a. Discovered that planets move around the Sun in elliptical orbits.
b. Proposed a heliocentric universe.
c. Developed a theory of gravity that explained orbital motion.
d. First to use a telescope to observe the heavens.
e. Obtained extensive and precise data on the positions of the planets by observing the sky.
30. In offering an alternative to the Earth-centered theory, Copernicus was motivated by
a. the fact that the Ptolemaic system couldn't explain retrograde motion of the planets
b. telescopic observations that revealed that Sun and Moon were not perfect
c. his discovery of three laws of motion that explained the orbits of the planets
d. the simplicity and elegance of the heliocentric theory
31. As a planet revolves around the Sun, it's speed is slowest
a. when closest the Sun
b. when furthest from the Sun
c. at perihelion
d. none of the above. The speed of a planet is always constant
32. Tycho Brahe is important in the history of astronomy because he
a. Discovered that planets move around the Sun in elliptical orbits.
b. Proposed a heliocentric universe.
c. Developed a theory of gravity that explained orbital motion.
d. Used a telescope to observe the heavens.
e. Obtained extensive and precise data on the positions of the planets by observing the sky.
33. Which of the following is NOT associated with Kepler's Laws of Planetary Motion?
a. The force of attraction between Sun and a planet depends on their masses, and inversely on the distance between them squared
b. A line from Sun to planet sweeps out equal areas in equal intervals of time
c. The square of a planet's orbital period around Sun is proportional to its average distance from Sun cubed
d. They were discovered by Kepler prior to the condemnation and imprisonment of Galileo
34. Poor seeing refers to
a. the problem of finding the star of interest out of the millions visible through telescopes
b. buildings and other obstructions near the observatory
c. clouds
d. the blurring of an image by movements of air in the atmosphere
35. The ___________ of a telescope is a measure of its ability to show fine detail and depends on the diameter of the objective.
a. light-gathering power
b. focal length
c. magnifying power
d. resolving power
e. spherical aberration
36. Light appears as different colors because the colors indicate different:
a. speeds of light
b. frequencies of light
c. amplitudes of light
d. magnetism of light
37. Which of the following statements regarding electromagnetic radiation is TRUE?
a. All wavelengths travel at different speed
b. Any wavelength can get through the radio window if it slows down
c. Radio wavelengths are longer than X-ray wavelengths
d. In general, ultraviolet radiation is less harmful than microwave radiation
38. The diagram below illustrates a ______________ telescope.
a. Coude focus
b. Cassegrain
c. Newtonian
e. Prime focus
39. In general, the primary function of a telescope is to
a. measure the wavelengths of the incoming types of radiation
b. separate out one type of radiation from another
c. capture and focus light
d. measure the amount of radiation produced inside of an object in space
40. Which of the following is the reason for building telescopes atop mountains?
a. Air turbulence is greatest from atop a mountain, so seeing conditions are better
b. Mountains are very easy to travel to and easy to build telescopes on.
c. There is less atmosphere between the observer and the celestial object being observed.
d. Astronomical objects are closer from atop a mountain, and therefore appear brighter
41. Often times, two or more radio telescopes are linked together electronically while studying the same object. This is primarily for the purpose of
a. verifying that the main telescope is tracking the correct object
b. increasing the focal length of the telescope, and thereby increasing the magnification
c. improving the resolution of the object being studied
d. allowing astronomers from different countries to share in the excitement of new discoveries
42. Radiation that has slightly longer wavelengths than that of x-rays:
a. infrared
b. ultraviolet
c. radio
d. gamma rays
43. CCDs are replacing photographic plates in telescopes because
a. they do not require as long an exposure time for the same brightness of image
b. photographic plates do not hold up under the cold temperatures on mountain tops
c. CCD's are less expensive to produce
d. they are sensitive to types of radiation that photographic plates are not
44. What is resolving power, and how is it improved?
a. The ability to magnify; the use of an eye piece with a short focal length.
b. The ability to collect light; the use of a larger telescope.
c. The ability to detect small detail; the use of a larger telescope.
d. The ability to detect small detail; the use of a smaller telescope.
45. When shopping for a telescope, what feature is the best indicator of the performance of the telescope?
a. The degree of magnification it is capable of
b. The focal length
c. The radius of the objective or mirror
d. The number of eyepieces that come with the telescope
46. When an electron jumps between two energy levels, the energy it absorbs or emits
a. is the same as the energy level difference
b. is less than the energy level difference
c. is at visible wavelengths
d. forms the Balmer series
47. Astronomers determine the chemical elements in a gas cloud by
a. detecting the black body radiation of the gas cloud
b. applying the Doppler effect
c. identifying the wavelengths of emission and/or absorption lines
d. obtaining the continuous spectrum of the gas cloud
48. In a laboratory, the hydrogen Balmer beta line has a wavelength of 486.10 nm. A star's spectrum reveals the same line to have a wavelength of 485.30 nm.
a. The star must be cooler than the hydrogen in the laboratory
b. The star is moving away from Earth
c. The electrons in the hydrogen atoms in the star have dropped down two energy levels
d. The star is moving toward the Earth
49. A red star appears red because
a. Earth's atmosphere emits more red light than other colors
b. of the Doppler effect
c. all colors coming from the star except blue are absorbed by the Earth's atmosphere
d. of the surface temperature of the star
50. The diagram below illustrates a light source, a gas cloud, and three different lines of sight. Along which line of sight would an observer see an emission spectrum?
a. 1
b. 2
c. 3
d. 2 and 3
e. none of them