astronomy 100 midterm 1 review (chapters 1-7)

a. 22800,000,000,000,000,000 miles

*CH1* A particular galaxy is about 3.8 million light-years away. Light travels at 6 trillion miles per year. How many miles distant is the galaxy? a. 22800,000,000,000,000,000 miles b. 22800 miles c. 22.8 miles d. 22800,000,000,000 miles e. 22800,000,000 miles

b. Earth, sun, solar system, Milky Way Galaxy, cluster of galaxies

*CH1* Choose the option which lists objects from smallest to largest size (left to right). a. Milky Way Galaxy, cluster of galaxies, Earth, sun, solar system b. Earth, sun, solar system, Milky Way Galaxy, cluster of galaxies c. Earth, Milky Way Galaxy, cluster of galaxies, solar system, sun d. solar system, Milky Way Galaxy, cluster of galaxies, Earth, sun e. sun, solar system, Milky Way Galaxy, cluster of galaxies, Earth

a. the Earth-moon system

*CH1* Consider the Earth-moon system, the solar system, the galaxy and the universe. Which has the least empty space relative to the size of the objects it is made of? a. the Earth-moon system b. the galaxy c. the universe d. the solar system

c. 80,000 years

*CH1* How long does it take light to cross the diameter of our Milky Way Galaxy? Pick the best answer. a. 1 second b. 8,000 years c. 80,000 years d. 4 years e. 8 minutes

d. 5,281km

*CH1* If a mile equals 1.609 km and Ganymede is 3282 miles in diameter, what is its diameter in kilometers? Choose the best answer. a. 3282 b. 7220 c. 1.609 d. 5281 e. 6236

d. 0.2 seconds

*CH1* Light from the sun takes 43 minutes to reach Jupiter. The sun is almost 13640 times farther from Jupiter than is Adrastea (one of the moons of Jupiter). How long does light from Adrastea take to reach Jupiter? a. 0.02 seconds b. 1.5 minutes c. 1.5 hours d. 0.2 seconds e. 0.2 minutes

d. 76.8

*CH1* Light from the sun takes 8 minutes to reach Earth. How long in minutes does it take to reach Saturn? Saturn is about 9.6 AU from the sun. Choose the best answer. a. 7.68 b. 2.40 c. 1.92 d. 76.8 e. 768

a. It is the sunset line because Earth rotates counterclockwise when viewed from above Earth's north pole.

*CH1* North is up in this figure. Can we tell whether the daylight and darkness line at the right is the sunset line or the sunrise line? a. It is the sunset line because Earth rotates counterclockwise when viewed from above Earth's north pole. b. It is the sunrise line because Earth rotates clockwise when viewed from above Earth's north pole. c. It is the sunrise line because Earth rotates counterclockwise when viewed from above Earth's north pole. d. It is the sunset line because Earth rotates clockwise when viewed from above Earth's north pole. e. No, we can't tell.

b. a group of several hundred billion stars of which our sun is a part

*CH1* The Milky Way is which of the following? a. not visible from Earth b. a group of several hundred billion stars of which our sun is a part c. a great cloudy haze of milk ringing our night sky d. a distant galaxy

a. filaments and walls

*CH1* The largest structures in the universe are which of the following? a. filaments and walls b. stars c. galaxies d. clusters of galaxies

d. kilometer

*CH1* Think about the following distance measurements: mile, kilometer, astronomical unit, and light-year. In scientific astronomical work, which distance measurement is most useful and most often used for distances ON a planet? a. mile b. astronomical unit c. light-year d. kilometer

d. astronomical unit

*CH1* Think about the following distance measurements: mile, kilometer, astronomical unit, and light-year. Which distance measurement is most useful in the solar system? a. light-year b. mile c. kilometer d. astronomical unit

a. light-year

*CH1* Think about the following distance measurements: mile, kilometer, astronomical unit, and light-year. Which distance measurement is the largest? a. light-year b. mile c. kilometer d. astronomical unit

d. kilometer

*CH1* Think about the following distance measurements: mile, kilometer, astronomical unit, and light-year. Which distance measurement is the smallest? a. mile b. astronomical unit c. light-year d. kilometer

a. The stars that appear largest in the figure are the brightest ones (in appearance).

*CH1* What does the size of star images in a photograph tell you about the stars? a. The stars that appear largest in the figure are the brightest ones (in appearance). b. The stars that appear largest in the figure are the closest ones. c. All of the choices are correct. d. The stars that appear largest in the figure are the biggest ones.

a. stars

*CH1* What forms in the great clouds of gas and dust in the spiral arms of a galaxy? a. stars b. voids c. superclusters d. galaxy clusters e. None of these choices are correct.

a.

*CH1* Which of the figures shown here is that of a single galaxy? a. b. c. d.

b. because they are so small and so far away

*CH1* Why is it difficult to detect planets orbiting other stars? a. because as far as we know, there aren't any b. because they are so small and so far away c. because they are so rare d. Actually, it is not difficult to detect planets orbiting other stars.

b. some electricity, because it is getting some sunlight, but less than when it is not in Earth's shadow

*CH2* A solar-powered spacecraft passed through Earth's shadow. In the outer part of the shadow, the penumbra, what does the spacecraft generate? a. as much electricity as when it is not in the shadow, because the outer part of the shadow does not block the sun b. some electricity, because it is getting some sunlight, but less than when it is not in Earth's shadow c. the same amount of electricity as when in the umbra d. no electricity at all, because it is getting no sunlight

d. a relatively bright star

*CH2* A star with an ancient Arabic name is which of the following? a. relatively dim b. was not known to the ancients c. invisible to the eye d. a relatively bright star

c. its relative brightness within its constellation

*CH2* A star's Greek letter designation tells you which of the following? a. that it was known to the ancients b. that it is a bright star c. its relative brightness within its constellation d. its absolute brightness

a. one Saros period later

*CH2* A total eclipse of the sun was visible from Australia on October 23, 1976. When would the next total eclipse be seen from a point about a third of the way around the world westward from Australia (at about the same southern hemisphere latitude)? a. one Saros period later b. three Saros periods later c. one synodic month later d. the next eclipse season

b. near the ecliptic and at full phase

*CH2* A total lunar eclipse occurs when the moon is which of the following? a. at new phase and at first quarter phase b. near the ecliptic and at full phase c. at full phase d. near the ecliptic e. at new phase

a. 21

*CH2* About how many days must elapse between the first-quarter moon and the next new moon? a. 21 b. 14 c. 365 d. 7 e. 28

c. (a) Ursae Majoris

*CH2* Based on how stars are named, which star is probably brightest? a. ϵ Ursae Majoris b. ϵ Scorpii c. (a) Ursae Majoris d. (a) Telescopiu

d. Gemini

*CH2* Based on this figure, in what constellation is the sun on July 1 each year? a. Cancer b. Sagittarius c. Aquarius d. Gemini e. Leo

d. Earth's orbit around the sun is less elliptical than the moon's orbit around Earth.

*CH2* Compare the range in angular size for the sun and moon shown in this figure. From these ranges we can conclude which of the following: a. Earth's orbit around the sun is more elliptical than the moon's orbit around Earth. b. Earth's orbit around the sun and the moon's orbit around Earth are both circular. c. Only one of the orbits is elliptical. d. Earth's orbit around the sun is less elliptical than the moon's orbit around Earth. e. We cannot conclude anything about the orbits.

c. It is a little cooler than in the southern hemisphere.

*CH2* Due to Earth's elliptical orbit, Earth is a little closer to the sun in January than in July. Because of this, which is true for summer in the northern hemisphere? a. It is exactly the same as in the southern hemisphere. b. It occurs in January. c. It is a little cooler than in the southern hemisphere. d. It is a little warmer than in the southern hemisphere.

b. It is a little cooler than in the northern hemisphere.

*CH2* Due to Earth's elliptical orbit, Earth is a little closer to the sun in January than in July. Because of this, which is true for winter in the southern hemisphere? a. It is exactly the same as in the northern hemisphere. b. It is a little cooler than in the northern hemisphere. c. It occurs in January. d. It is a little warmer than in the northern hemisphere

d. 7

*CH2* During solar eclipses, solar prominences are often seen extending 2 minutes of arc or 1/30 of a degree from the edge of the sun's disk. Knowing that the sun is about 1/2 of a degree in angular size in the sky and that it is about 100 times Earth's diameter in kilometers, how far does a large prominence extend, in Earth diameters? a. 105 b. 70 c. 2 d. 7 e. 1/30

a. 90° - 30° + 23.4°

*CH2* For a latitude of 30° north, what is the angle between the southern horizon and the noon sun at the summer solstice? a. 90° - 30° + 23.4° b. 90° + 30° + 23.4° c. 30° + 23.4° d. 30° - 23.4°

d. 15.8 times brighter

*CH2* How many times brighter is a magnitude 1.0 star than a magnitude 4.0 star? a. 0.25 as bright b. 1.20 as bright c. 4.0 times brighter d. 15.8 times brighter

e. 3

*CH2* How many times larger than the moon is the diameter of Earth's umbral shadow at the moon's distance? (Hint: See the image above.) It is _____ times the moon's size. a. 30 b. 100 c. 0.3 d. 300 e. 3

d. third quarter

*CH2* Identify the phase of the moon if at sunrise the moon is high in the southern sky for a mid-northern hemisphere observer. a. first quarter b. new moon c. waxing crescent d. full moon e. third quarter f. waning crescent

e. full moon

*CH2* Identify the phase of the moon if at sunset the moon is near the eastern horizon. a. new moon b. first quarter c. third quarter d. waning crescent e. full moon d. waxing crescent

c. 27.3 days (sidereal period)

*CH2* If on March 1st the full moon is near the star Spica, when will it next be near Spica? a. 365.25 days (one year) b. 200 million years (one Galactic orbital period) c. 27.3 days (sidereal period) d. 29.5 days (synodic period

b. waning crescent

*CH2* If on March 1st the full moon is near the star Spica, when will the moon next be full? a. waning gibbous b. waning crescent c. waxing gibbous d. waxing crescent e. new

a. 4.20

*CH2* If one star is 48 times the flux ratio of another star, how many magnitudes brighter is it? a. 4.20 b. 2.5 c. 528 d. 48 e. 42.0

a. 1.9

*CH2* If one star is 5.5 times the flux ratio of another star, how many magnitudes brighter is it? Choose the best answer. a. 1.9 b. 5.5 c. 3.7 d. 11.0 e. 0.7

d. 400,000

*CH2* If the apparent visual magnitude of the sun is -26.74 and that of the full moon is -12.74 , what is the light flux ratio of sunlight to full moonlight received by Earth? a. 100 b. 40 c. 10,000 d. 400,000 e. 4000

e. 1585 to 1

*CH2* If two stars differ by 8 magnitudes, what is the flux ratio of the brighter to the dimmer star? a. 80 to 1 b. 2.5 to 1 c. 1057 to 1 d. 8.0 to 1 e. 1585 to 1

a. 100 to 1

*CH2* If two stars differ in brightness by 5 magnitudes, what is the flux ratio of the brighter to the less bright star? a. 100 to 1 b. 120 to 1 c. 80 to 1 d. 60 to 1 e. 20 to 1

c. full

*CH2* Imagine you're an astronaut standing on the moon and looking back at Earth. What phase would Earth have when the moon is new as seen by an Earth observer? a. first quarter b. third quarter c. full d. new

d. at all locations north of 23.4° north latitude

*CH2* In this figure it is apparent that the radius of the precession circle is 23.4°. At what latitude on Earth is the entire precession path currently above the horizon? a. at all locations north of 66.6° north latitude b. only at Earth's north pole c. at all locations in the northern hemisphere d. at all locations north of 23.4° north latitude e. at all locations north of 47° north latitude

c. full

*CH2* Look at the Phases of the Moon diagram and visualize yourself on Earth looking at the moon. Which lunar phase would rise in the eastern sky at dusk? a. first quarter b. third quarter c. full d. new

a. Light output and distance cannot be determined from a star's apparent visual magnitude alone.

*CH2* The apparent visual magnitude of star A is 2 and the apparent visual magnitude of star B is 1. Based on this information which statement below must be true? a. Light output and distance cannot be determined from a star's apparent visual magnitude alone. b. Star A emits more light than star B. c. Star B emits more light than star A. d. Star B is closer than star A. e. Star A is closer than star B

c. The points of the moon's crescent always point away from the sun, so the sun should be visible in the sky

*CH2* The postage stamp below shows a crescent moon in a starry night sky. What is wrong with the depiction of the moon in this picture? a. The moon is close to the horizon in the early morning. b. The points of the moon's crescent always point toward the sun, so we should see the sun setting on the horizon. c. The points of the moon's crescent always point away from the sun, so the sun should be visible in the sky. d. The moon is close to the horizon in the early evening.

e. All of these choices are correct.

*CH2* The precession of Earth's rotational axis causes the location of the _________ to change. a. north celestial pole and south celestial pole b. vernal equinox and autumnal equinox c. summer solstice and winter solstice d. north and south celestial poles and vernal and autumnal equinoxes e. All of these choices are correct.

c. about 1.9° or 6,850 seconds of arc

*CH2* Using the small-angle formula, what is the angular diameter of Earth as seen from the moon? a. about 3.2° or 11,520 seconds of arc b. about 10.1° or 36,360 seconds of arc c. about 1.9° or 6,850 seconds of arc d. about 1.0° or 3,426 seconds of arc

c. The sun is higher in the sky in the summer.

*CH2* What is a reason for winter days being colder than summer days? a. The sun is warmer in the summer. b. The sun is up for less time in the summer. c. The sun is higher in the sky in the summer. d. The sun is closer in the summer.

a. 90°

*CH2* What is the angular distance from the north celestial pole to the sun at vernal equinox? a. 90° b. 66.5° c. 180° d. 0° e. 113.5°

a. They use the celestial sphere, a scientific model, to explain motions of the stars.

*CH2* What is true about astronomers? a. They use the celestial sphere, a scientific model, to explain motions of the stars. b. They used to use the celestial sphere as a scientific model. c. They cannot use the celestial sphere because it does not represent reality. d. They can observe the entire celestial sphere from any location on Earth.

b. new moon, waxing crescent, first quarter, waxing gibbous, full moon

*CH2* Which list below ranks the phases of the moon from dimmest to brightest left to right? a. new moon, first quarter, waxing crescent, waxing gibbous, full moon b. new moon, waxing crescent, first quarter, waxing gibbous, full moon c. waxing gibbous, waxing crescent, full moon, new moon, first quarter d. waxing crescent, first quarter, waxing gibbous, new moon, full moon e. Actually, these are phases of the sun, not the moon.

c. -1

*CH2* Which magnitude star is brightest? a. 1 b. 2 c. -1 d. 0

d. Polaris, Sirius, Venus, full moon

*CH2*Use the figure above to find which of the following lists of objects is dimmest to brightest (from left to right): a. Venus, full moon, Polaris, Sirius b. Sirius, Venus, full moon, Polaris c. full moon, Polaris, Sirius, Venus d. Polaris, Sirius, Venus, full moon e. They are all of equal brightness.

b. It occurs during winter in the southern hemisphere.

*CH2*Which of the following is true for summer in the northern hemisphere? a. It occurs when the south pole is pointing toward the sun. b. It occurs during winter in the southern hemisphere. c. It is longer than summer in the southern hemisphere. d. It occurs when the Earth's north pole is pointing straight at the sun.

b. a large angular diameter of 12.5 seconds of arc when it is a crescent

*CH3* A telescope showed that Mercury has a large angular diameter of 12.5 seconds of arc when it is a crescent; a small angular diameter of 4.6 seconds of arc when it is nearly full and, finally, when Mercury is "half full," an angular size of 11.9 seconds of arc. At which point described below is Mercury closest to the Earth? a. a small angular diameter of 4.6 seconds of arc when it is nearly full b. a large angular diameter of 12.5 seconds of arc when it is a crescent c. "half full," with its angular size of about 11.9 seconds of arc

a. a deferent

*CH3* Below is a postage stamp with a picture of a scientist holding an astronomical model. What is the larger circle in his model? a. a deferent b. an epicycle c. Either an epicycle or a deferent, depending on which planet they are for. d. None of these choices are correct.

c. an epicycle

*CH3* Below is a postage stamp with a picture of a scientist holding an astronomical model. What is the smaller circle in his model? a. a deferent b. Either an epicycle or a deferent, depending on which planet they are for. c. an epicycle d. None of these choices are correct

d. 0.90

*CH3* Compare the force of gravity on the surface of Uranus with the force of gravity at Earth's surface. Mass of Uranus is 14.5 that of the Earth and its radius is 4.01 that of the Earth. a. 4.01 b. 14.50 c. 3.62 d. 0.90

b. It was possible in Copernican theory, but not Ptolemaic theory.

*CH3* Galileo made several important telescopic discoveries. How did Galileo's telescopic discovery that Venus went through the same cycle of phases as the moon contradict Ptolemaic theory? a. It showed that a heavenly body was not perfect. b. It was possible in Copernican theory, but not Ptolemaic theory. c. It showed that not everything orbited Earth. d. Actually, it did not contradict Ptolemaic theory.

a. circles the sun

*CH3* Galileo's telescope showed him that Venus has a large angular diameter (61 seconds of arc) when it is a crescent and a small angular diameter (10 seconds of arc) when it is nearly full. When Venus is "half full," its angular size is about 59 seconds of arc. This sequence of phases and angular sizes indicates that Venus: a. circles the sun. b. circles the Earth staying a fixed distance closer to the Earth than the sun. c. stays a fixed distance from the Earth always closer than the sun. d. stays a fixed distance from the Earth, always farther than the sun.

a. Inner planets orbit the sun faster and pass outer planets as they orbit around the sun.

*CH3* How did Nicolaus Copernicus account for the retrograde motion of the planets? a. Inner planets orbit the sun faster and pass outer planets as they orbit around the sun. b. Planets slow down, stop, and then reverse their orbital direction around the Earth. c. Each planet moves on an epicycle that in turn moves on a deferent that circles around Earth. d. The sun and moon orbit Earth, whereas all the other planets orbit the sun. e. None of these choices are correct.

d. 173 years

*CH3* If a planet has an average distance from the sun of 31 AU, what is its orbital period in years? a. 0.32 year b. 1726 years c. 31 years d. 173 years e. 29791 years

c. 2.8

*CH3* If a space probe is sent into an orbit around the sun that brings it as close as 1.0 AU and as far away as 3 AU, what will be its orbital period in years? a. 8.0 b. 16 c. 2.8 d. 32 e. 1

e. 5.5 years

*CH3* If the semimajor axis of a planet is 3.1 AU, what is its orbital period? a. 9.6 years b. 3.1 years c. 30 years d. It cannot be determined from the given information. e. 5.5 years

a. Venus

*CH3* If you lived on Mars, which planet would be visible as a crescent phase? a. Venus b. Saturn c. Jupiter d. Uranus e. Mars

e. All of these choices are correct

*CH3* If you lived on Mars, which planets would exhibit retrograde motion? a. Neptune b. Uranus c. Saturn d. Jupiter e. All of these choices are correct

b. because they were never seen very far from the sun in the sky

*CH3* In Ptolemy's mathematical model of planetary motion, a planet was on a circular path, known as an epicycle, whose center was on another circular path, a deferent, that was centered on Earth. Why did the centers of the epicycles of Mercury and Venus have to remain on the line between Earth and the sun? a. because they moved in opposite directions to the other planets b. because they were never seen very far from the sun in the sky c. because they were closer to Earth than the other planets d. because, unlike the other planets, they were considered to orbit the sun

d. all of the known planets

*CH3* In Ptolemy's mathematical model of planetary motion, a planet was on a circular path, known as an epicycle, whose center was on another circular path, a deferent, that was centered on Earth. Which planets' motions were described with epicycles in the Ptolemaic system? a. Mars, Jupiter, and Saturn b. Ptolemy's system did not use epicycles. c. Mercury and Venus d. all of the known planets

a. The mass of the sun plus the mass of a planet is nearly one solar mass.

*CH3* Newton's form of Kepler's law can be written as (Msun + Mplanet)P^2y = a3, where the masses of the sun and planet are in units of solar masses, the period is in units of years, and the semimajor axis is in astronomical units. Why is Kepler's form of his third law nearly identical to Newton's form? a. The mass of the sun plus the mass of a planet is nearly one solar mass. b. Both forms are very similar in that they have periods and semimajor axes in units of years and astronomical units respectively. c. The mass of each planet is very large. d. The mass of the sun plus the mass of a planet is nearly one solar mass and the mass of each planet is very large. e. All of these choices are correct.

d. orbit period, orbit radius, and mass of central body

*CH3* P^2 = 4(3.14)^2r^3/(GM) is the equation relating the variable physical quantities __________. a. orbit period, and mass of central body only b. orbit period, and radius of orbit only c. orbit radius, and mass of central body only d. orbit period, orbit radius, and mass of central body

c. The amount of force on Planet Q is 1/25 the force on Earth.

*CH3* Suppose that Planet Q exists such that it is an identical planet to Earth yet orbits the sun at a distance of 5 AU. How does the amount of gravitational force exerted on Planet Q by the sun compare to the amount of gravitational force exerted on Earth by the sun? a. The amount of force on Planet Q is 25 times the force on Earth. b. The amount of the two forces is the same. c. The amount of force on Planet Q is 1/25 the force on Earth. d. The amount of force on Planet Q is 5 times the force on Earth. e. The amount of force on Planet Q is 1/5 the force on Earth

e. The new ellipse is a circle.

*CH3* The figure shown here illustrates how to draw an ellipse with two tacks and a loop of string. Imagine constructing a new ellipse using the same string but with the distance between the two pins reduced to zero. Which statement below is true? a. The new ellipse is more elliptical than the original ellipse. b. The new ellipse is more circular than the original ellipse without being a perfect circle. c. The semimajor axis of the new ellipse is longer than that of the original ellipse. d. The new ellipse is actually a flat line. e. The new ellipse is a circle.

a. Nicolaus Copernicus

*CH3* The phases of Venus observed by Galileo support the model of the universe presented by which of the following? a. Nicolaus Copernicus b. Aristotle c. Claudius Ptolemy d. Aristotle and Claudius Ptolemy e. All of these choices are correct.

d. 19.2

*CH3* Uranus orbits the sun with a period of 84.33 years. What is its average distance from the sun in AU? a. 7111 b. 369.8 c. 84.33 d. 19.2

c. that it must be central

*CH3* What does Aristotle's explanation of why objects fall to Earth suggest about Earth's position in the universe? a. that it could be central b. that is must not be central c. that it must be central d. Aristotle's explanation of gravity has nothing to do with Earth's position in the universe.

c. 66.6°

*CH3* What is the angular distance from the south celestial pole to the sun at summer solstice? a. 180° b. 0° c. 66.6° d. 90° e. 113.6°

a. 3932

*CH3* What is the circular velocity in m/s of an Earth satellite 2.58 * 10^7m from Earth's center? (Hints: The circular orbital speed is equal to (square root) GM/orbital radius, Earth's mass is 5.98 * 10^24kg and G = 6.67 * 10^-11 in mks units a. 3932 b. 5561 c. 1573 d. 1521

e. new, crescent, quarter, gibbous, and full phases

*CH3* What phases of Venus were observed by Galileo? a. quarter and gibbous phases only b. gibbous and full phases only c. new and crescent phases only d. crescent and gibbous phases only e. new, crescent, quarter, gibbous, and full phases

a. a theory

*CH3* Which is a system of rules and principles that can be applied to a wide variety of circumstances? a. a theory b. a hypothesis c. a natural law d. None of these choices are correct.

b. Both objects orbit the center of mass of the system, with the more massive object having a smaller orbit.

*CH3* Which is really true about the center of the orbit of a two-object system? a. The less massive object orbits in a path that is centered on the center of the more massive object. b. Both objects orbit the center of mass of the system, with the more massive object having a smaller orbit. c. The two objects orbit the point halfway between them. d. Both objects orbit the center of mass of the system, with the more massive object having a larger orbit.

c. figure b (right)

*CH3* Which of these two figures matches the phases of Venus observed by Galileo? a. He only observed Venus in its full phase. b. figure a (left) c. figure b (right) d. He only observed Venus in its first quarter phase. e. He could not see phases because his telescopes were not powerful enough.

a. All of these choices are correct.

*CH3* Why did Newton conclude that some force had to pull the moon toward Earth? a. All of these choices are correct. b. The moon's orbital motion is a curved fall around Earth. c. The moon has an acceleration toward Earth. d. The force and acceleration in Newton's second law must have the same direction. e. The moon has an acceleration toward Earth and the force and acceleration in Newton's second law must have the same direction.

c. because he believed the sphere to be the most perfect geometrical form

*CH3* Why did Plato propose what he did about heavenly motion and the shape of heavenly objects? a. because of the shape of the sun and the moon b. because of his telescopic observations c. because he believed the sphere to be the most perfect geometrical form d. because Earth seems to be a disk around us, and the sky appears to be a spherical shell above us

b. If Earth is the natural place of everything that falls, then it must be central.

*CH3* Why does Aristotle's explanation of why objects fall to Earth suggest what it does about Earth's position in the universe? a. If Earth is the natural place of everything that falls, then it must not be central. b. If Earth is the natural place of everything that falls, then it must be central. c. Earth's gravity is only a local effect; it is not universal. d. Aristotle's explanation of gravity has nothing to do with Earth's position in the universe.

e. One uses top lens for the primary and bottom lens for the eyepiece.

*CH4* If you were to make a telescope using the two lenses shown here, which lens should you use for the primary (objective) and which for the eyepiece? a. One uses top lens for the primary and bottom lens for the eyepiece and one uses top lens for the eyepiece and bottom lens for the primary, depending on the type of telescope. b. These lenses do not have the correct shape to be used in a telescope. c. One uses top lens for the eyepiece and bottom lens for the primary. d. There is not enough information provided to answer. e. One uses top lens for the primary and bottom lens for the eyepiece.

a. short wavelengths

*CH4* In this figure you can see that different wavelengths of light are refracted (bent) by different amounts. Which wavelengths are bent by the greatest amount? a. short wavelengths b. long wavelengths c. wavelengths intermediate between long and short wavelengths d. It cannot be determined from the figure. e. None of these choices are correct.

c. CCD

*CH4* Not long ago, an astronomer said: "Some people think I should give up photographic plates." What device could replace photographic plates in astronomy? a. photometer b. spectrograph c. CCD d. false-color imager

a. There would be some chromatic aberration.

*CH4* Telescope mirrors have a reflective coating on their front surface as shown here. What major problem would be introduced if the reflective coating were beneath the glass surface? a. There would be some chromatic aberration. b. Light would be absorbed by the glass. c. The image would be blurry. d. Light pollution would distort the image. e. All of these choices are correct.

c. false colors that represent areas of different intensity within the image.

*CH4* The image below is an X-ray image of an exploded star. The colors in the image are: a. regions of different temperature within the object. b. the actual colors of the object. c. false colors that represent areas of different intensity within the image. d. caused by atmospheric turbulence.

b. 0.192 m

*CH4* What is the wavelength of radio waves transmitted by a radio station with a frequency of 1,560 million cycles per second? Light travels with a speed of about 300,000 km/s or 300,000,000 m/s. a. 300,000 m b. 0.192 m c. 5.2 m d. 300,000,000 m e. 1560 m

b. It divides light into the individual components of its spectrum.

*CH4* Which is true about a prism spectrograph? a. The prism has replaced the grating as the operative element in the spectrograph. b. It divides light into the individual components of its spectrum. c. It is not caused by refraction. d. All of these choices are true.

d. blue, green, yellow, red

*CH4* Which list has the colors of visible light in order of increasing wavelength from left to right? a. yellow, red, blue, green b. green, yellow, red, blue c. red, blue, green, yellow d. blue, green, yellow, red e. blue, green, red, yellow

d. far UV to X-ray

*CH4* Which of the different telescopes designed for the following specific types of electromagnetic waves has to be at the highest altitude from the surface of the Earth to be useful? a. visible b. radio c. near (to visible) infrared d. far UV to X-ray

d. radio, infrared, visible, ultraviolet, gamma-ray

*CH4* Which of the following lists has the types of electromagnetic radiation in order of decreasing wavelength from left to right? a. ultraviolet, gamma-ray, radio, infrared, visible b. visible, ultraviolet, gamma-ray, radio, infrared c. infrared, visible, ultraviolet, gamma-ray, radio d. radio, infrared, visible, ultraviolet, gamma-ray

c. red, yellow, green, blue

*CH4* Which of the lists below has the colors of visible light in order of increasing frequency from left to right? a. green, blue, red, yellow b. yellow, green, blue, red c. red, yellow, green, blue d. blue, red, yellow, green

a. long wavelength light

*CH4* Which reason for building a large telescope applies only to radio telescopes? a. long wavelength light b. collect more light c. better resolution d. All of these are good reasons to build a big optical or radio telescope

e. light-gathering power and resolving power

*CH4* Which theoretical power of an optical telescope is determined by the diameter of the primary mirror or lens? a. light-gathering power b. resolving power c. magnifying power d. light-gathering power and magnifying power e. light-gathering power and resolving power

b. convection

*CH5* What type of energy transport is occurring just below the photosphere? a. conduction b. convection c. We do not know, since we cannot see below the photosphere. d. radiation