PH109 Exploring the Universe, Test #1, Fall 2000
NAME______
Please indicate the best answer to the following question on the answer sheet provided. Each question is worth 2 points unless noted otherwise.
1. How many centimeters are there in one meter?
a. 1, b. 10, c. 100, d. 1,000, e. 1 x 106
2. Scientific notation is used in science because
a. it makes it easy to write big or small numbers., b. all astronomical distances are expressed in metric units.
c. it makes conversions between units easy., d. all of the above, e. none of the above
3. The average distance from Earth to the sun is
a. 1 ly, b. 1 million km, c. 1 million miles, d. 1 billion km, e. 1 AU
4. If the nearest star is 4.2 light-years away, then
a. the star is 4.2 million AU away., b. the light we see left the star 4.2 years ago.
c. the star must have formed 4.2 billion years ago., d. the star must be very young.
5. The radius of the moon's orbit is about ______times larger than the radius of Earth.
a. 0.6, b. 6, c. 60, d. 600, e. 6000
6. Seen from the northern latitudes, the star Polaris
a. is never above the horizon during the day., b. always sets directly in the west.
c. is always above the northern horizon., d. is never visible during the winter.
7. An observer on Earth's equator would find
a. Polaris directly overhead, b. Polaris 40° above the northern horizon.
c. the celestial equator coincides with the horizon., d. the celestial equator passing directly overhead.
8. 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
9. The magnitude scale
a. originated just after the telescope was invented, b. was devised by Galileo.
c. can be used to indicate the apparent intensity of a celestial object., d. is no longer used today.
10. The apparent visual magnitude of a star is 7.3. This tells us that the star is
a. one of the brighter stars in the sky., b. not visible with the unaided eye.
c. bright enough that it would be visible even during the day, d. very far from Earth.
11. An observer in the Northern Hemisphere watches the sky for several hours. Due to the motion of Earth, this observer notices that the stars near the north celestial pole appear to move
a. counter clockwise., b. clockwise., c. from left to right., d. from right to left., e. nearly vertically upward.
12. Which star in the table below would appear the brightest to an observer on Earth?
a. a Cet, b. a CMa , c. Nim, d. r Per, e. d Dra
13. You live at a latitude of 73° N. What is the angle between the northern horizon and the north celestial pole?
a. 73°, b. 27°, c. 17°, d. 231/2°, e. 5°
14. If the north celestial pole appears on your horizon, what is your latitude?
a. 90° N, b. 90° S, c. 0°, d. 45° N
15. An observer in the Northern Hemisphere takes a time exposure photograph of the night sky. If the illustration below depicts the photograph taken by the observer, which direction was the camera pointing?
a. straight north, b. straight east, c. straight south, d. straight west, e. straight up, directly overhead
16. The sun moves
a. about one degree westward each day., b. about one degree eastward each day.
c. about 360 degrees westward each day., d. about 360 degrees eastward each day.
17. At what two celestial locations do the celestial equator and ecliptic coincide?
a. winter solstice and summer solstice, b. vernal equinox and autumnal equinox
c. they coincide at all points because they are the same., d. north celestial pole and south celestial pole
18. Northern Hemisphere winters are colder than Northern Hemisphere summers because
a. Earth is closer to the sun during the summer.
b. the snow that falls in the northern latitudes cools Earth during the winter.
c. the light from the sun shines more directly on the Northern Hemisphere during the summer.
d. the period of sunlight is longer during the summer than during the winter.
e. Both the light from the sun shines more directly on the Northern Hemisphere during the summer, and the period of sunlight is longer during the summer than during the winter.
19. 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
20. On the vernal equinox the sun is
a. 231/2° north of the celestial equator., b. 231/2° south of the celestial equator.
c. on the celestial equator, d. closest to the north celestial pole.
21. Spring tides occur
a. at new moon and first quarter moon., b. at first quarter and third quarter moons.
c. at new moon and full moon., d. at third quarter and full moons.
22. A waxing crescent moon is visible
a. near the eastern horizon just before sunrise., b. near the eastern horizon just after sunset.
c. near the western horizon just before sunrise, d. near the western horizon just after sunset.
23. The first quarter moon rises
a. at about noon., b. at sunset., c. at sunrise., d. at about midnight.
24. Total lunar eclipses always occur at the time
a. of new moon., b. of full moon., c. either equinox., d. either solstice., e. that the sun is directly overhead.
25. A(n) ______is a circle whose center is located on the circumference of another circle.
a. equant, b. deferent, c. retrograde loop, d. ellipse, e. epicycle
26. The Copernican system was no more accurate than the Ptolemaic system in predicting the positions of the planets because
a. the Copernican system used the old value for the radius of Earth.
b. Copernicus had been unable to detect parallax.
c. the Copernican system included uniform circular motion.
d. in the Copernican system only Mercury and Venus orbit the sun, all other planets orbited Earth.
e. Copernicus used inaccurate data from Ptolemy's system.
27. Galileo's observations of the gibbous phase of Venus proved
a. that Venus orbited the sun., b. that Earth orbited the sun.
c. that all of the planets orbited the sun., d. that the moon orbited Earth.
28. Galileo's telescopic discoveries of mountains on the moon and spots on the sun were controversial because
they suggested that the sun and moon
a. were the same kind of object., b. were not perfect spheres.
c. were inhabited., d. orbited each other., e. did not orbit Earth.
29. Tycho Brahe's greatest contribution to astronomy was
a. his model of the universe., b. his telescopic observations.
c. his discovery of three laws of motion., d. his 20 years of careful observations of the planets.
30. Newton concluded that some force had to act on the moon because
a. a force is needed to keep the moon in motion., b. a force is needed to pull the moon outward.
c. a force is needed to pull the moon away from straight-line motion., d. the moon moved at a constant velocity.
31. Kepler's second law implies that
a. a planet should move at its greatest speed when it is closest to the sun.
b. the most massive planets will have the greatest speed in their orbits.
c. the speed of a planet in its orbit depends on the size of the epicycle.
d. the mass of the planet determines how far the planet is from the sun.
e. the deferent and the epicycle have to be attached to the sun and not Earth.
32. Gravity obeys an inverse square relation. This implies that the force due to gravity between two masses
a. will increase as the distance between the two masses increases.
b. will decrease as the square of the distance between the two masses increases.
c. will cause the two masses to move away from each other.
d. will cause the two masses to move in a straight line.
e. will cause the two masses to orbit each other.
33. ______has (have) wavelengths that are longer than visible light.
a. Gamma-rays, b. Ultraviolet light, c. Infrared radiation,
d. X-rays, e. Gamma-rays, Ultraviolet light, and X-rays.
34. Astronomers build telescopes on tops of mountains because
a. there is less air to dim the light., b. There is less air to dim the light, and the seeing is better.
c. CCDs work better when there is less oxygen in the air., d. the seeing is better.
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. A telescope that suffers from chromatic aberration and has a low light gathering power is most likely,
a. a small diameter reflecting telescope., b. a small diameter refracting telescope.
c. a large diameter refracting telescope., d. a large diameter reflecting telescope.
37. The neutral hydrogen atom consists of
a. one proton and one neutron., b. one proton.,
c. one proton, one neutron, and one electron., d. one proton and one electron.
38. A plot of the continuous spectra of five different stars
are shown in the figure below. Based on these spectra,
which of the stars is the hottest?
a. Star A, b. Star B, c. Star C, d. Star D, e. Star E
39. The two most abundant elements in the sun are
a. nitrogen and oxygen., b. hydrogen and helium., c. sulfur and iron., d. carbon and hydrogen.
40. You are standing near a railroad track and a train is moving toward you at 60 mph and blowing its horn. What will you notice as the train moves past you?
a. As the train approaches, the horn will sound lower in pitch than when it is moving away.
b. As the train approaches, the horn will sound higher in pitch than when it is moving away.
c. There will be no change in the pitch of the horn as it moves by.
d. The horn will get louder as the train moves away from you.
e. The horn will get quieter as the train moves toward you.
41. The table below lists the spectral types for each of five stars. Which star in this table would have the lowest surface temperature?
a. a For, b. o Cet, c. 35 Ari, d. g Tri, e. x Per
42. Which of the following types of electromagnetic radiation has the highest frequency?
a. x-rays, b. visible light, c. radio, d. gamma-rays, e. infrared radiation
43. What is the ratio of the light gathering power of a 10 m telescope to that of a 1 meter telescope?
a. 10 to 1, b. 1 to 10, c. 100 to 1, d. 1 to 100, e. 3.2 to 1
44 . When looking down upon the Earth from the North Celestial Pole, in what direction does it rotate?
a. counter clockwise, b. clockwise, c. cannot determine, d. does not appear to rotate
45. At anyone given time, how much of the Moon is illuminated by the Sun?
a. 1/2, b. all, c. 1/4, d. depends on its phase
46. The tropic of cancer is the imaginary line north of the Equator where it appears the Sun is overhead during the summer solstice. In degrees of Latitude, how far from the equator in the Tropic of Cancer?
a) 33.33 degrees, b) 23.5 degrees, c) depends on the season, d) 23.5 radians
47. Why are there 12 months in a year on our current calendar?
a. the year is easily divisible into 12 parts, b. 12 was considered a "magic" number,
c. there are 12 lunar cycles in a year, d. because there are 12 Zodiac signs in the sky
48. Approximately what is the azimuth (AZ) and elevation (EL) of the planet Venus located 1/3 of the way up in the southwest?
a. AZ=230o, EL=30o, b. AZ=30o, EL=230o, c. Az=110o, EL=30o, d. AZ=30o, EL=110o
49. The distance between two massive objects quadruples. By what factor is the gravitational force between them changed?
a. one half, b. one fourth, c. one eighth, d. one sixteenth
50. Given the equation C=, where C=the speed, =is the frequency, and =the wavelength, if a wave has speed 20 m/s and frequency 4 Hz. What is its wavelength?
a. 80 m, b. 20 m, c. 5 m, d. 4 m