astronomy chapter 4-6 vocab

Arrays of radio telescopes can produce much better resolution than single-dish telescopes because they work based on the principle of Choose one: A. reflection. B. diffraction. C. refraction. D. interference.

d

When an electron moves from a higher energy level to a lower energy level in an atom, Choose one: A. a continuous spectrum is emitted. B. the atom is ionized. C. a photon is absorbed. D. a photon is emitted.

d

What happens to the appearance of an object as it gets hotter? Choose one or more: A. The object gets brighter. B. The object gets fainter. C. The object gets redder. D. The object gets bluer.

A, d

The bright, colorful "stripes" of a rainbow such as the one shown here follow a particular order. Rank each color of the rainbow by how much energy is carried by its electromagnetic waves, from highest to lowest. options: yellow, orange, red, blue

1. blue 2. yellow 3. orange 4. red

Earth's tides are caused by the gravitational pull of both the Sun and the Moon. Rank the strength of the combined tidal forces exerted on Earth, and thus the height of the tides, when the Moon is in the following phases listed, weakest to strongest new moon, first quarter, waning gibbous

1. first quarter 3. waning gibbous 3. new moon

Rank the types of radiation in order of their energy, from least to greatest. Items options: gamma rays, red visible light, x-rays, blue visible light, infrared, radio waves

1. radio waves 2. infrared 3. red visible light 4. blue visible light 5. x-rays 6. gamma rays

The Earth rotates on its axis once every 24 hours. Due to this motion, roughly how many full hours would you expect to pass between two subsequent high tides at any given location on the Earth?

12

In practice, the smallest angular size that one can resolve with a 10-inch telescope is governed by the Choose one: A. blurring caused by Earth's atmosphere. B. magnification of the telescope. C. size of the primary mirror. D. diffraction limit of the telescope.

a

As two objects orbit one another, they are always Choose one: A. on opposite sides of the center of mass, traveling in opposite directions in space. B. on opposite sides of the center of mass, traveling in the same direction in space. C. on the same side of the center of mass, traveling in opposite directions in space. D. on the same side of the center of mass, traveling in the same direction in space.

a

F is the force that is causing the object to accelerate. In the case of dropping objects from a height, the force that causes them to accelerate toward the Earth is gravity. If the acceleration of objects dropped from a height does not depend on the object's mass (as shown by Galileo's experiment), what does this imply about the force of gravity? Choose one: A. The force of gravity increases with increased mass. B. The force of gravity is constant with mass. C. Nothing can be determined about gravity from this information. D. The force of gravity decreases with increased mass.

a

For a system in which a planet orbits a star, the center of mass is located Choose one: A. along the line between the planet and the star, closer to the star. B. along the line between the planet and the star, closer to the planet. C. at the center of the star. D. at the center of the planet.

a

Given this, what would observer 2 (who does not see the star through the gas) observe in the spectrum of the cloud of gas in the picture above? Select the appropriate spectrum below. (see ch5 q7)

a

If an object crosses from farther to closer than the Roche limit, it Choose one: A. may be torn apart. B. can no longer be seen. C. begins to accelerate very quickly. D. slows down.

a

If you went to Mars, your weight would be Choose one: A. lower because Mars has lower mass and a smaller radius that together produce a lower gravitational force. B. higher because you are closer to the center of the planet. C. the same as on Earth. D. lower because Mars has two small moons instead of one big moon, so there's less tidal force.

a

Imagine that Earth were in a stable orbit at its current distance from the Sun, but around a different star that had twice the mass of the Sun. Which of the following would have to be true? Choose one: A. Earth's year would be shorter. B. Earth's year would be longer. C. Earth's mass would be lower. D. Earth's mass would be higher.

a

Imagine that you observe a star/planet system, edge-on. When the planet is moving away from Earth, the light from the star is Choose one: A. blueshifted. B. redshifted.

a

Select the spectrum that most closely matches the one you would expect to observe from the light source at the end of the Explanation in the AstroTour, after the light has passed through the hypothetical gas. (see ch 5 q 6)

a

The "square" in the inverse square law for intensity of light means that Choose one: A. at three times the distance, the intensity is 1/9 as great. B. at three times the distance, the intensity is nine times greater. C. at three times the distance, the intensity is three times greater. D. at three times the distance, the intensity is 1/3 as great.

a

Two stars are of equal luminosity. Star A is 3 times as far from you as star B. Star A appears _________ star B. Choose one: A. one-ninth as bright as B. 3 times brighter than C. the same brightness as D. one-third as bright as E. 9 times brighter than

a

Venus has about 80 percent of Earth's mass and about 95 percent of Earth's radius. Your weight on Venus will be Choose one: A. 10 percent less than on Earth. B. 10 percent more than on Earth. C. 20 percent more than on Earth. D. 20 percent less than on Earth.

a

Why don't we see cars as bluer when they approach and redder when they recede? Choose one: A. They are too slow. B. They are too small. C. We are too far away from them. D. Our eyes can't distinguish between red and blue.

a

Study the figure, which shows how someone on Earth can view Jupiter's moon's eclipses when Earth is closer to or farther from Jupiter, and determine which of the following are correct. (see ch 5 q2) Choose one or more: A. If light has infinite speed, an eclipse would be seen to happen at the same time regardless of how far away Earth is from Jupiter. B. If light has finite speed, it would take longer for it to travel from Jupiter to Earth when Earth is farther from Jupiter. C. If light has finite speed, an eclipse would be seen to happen at a later time when Earth is closer to Jupiter than when it is farther away from Jupiter.

a, b

Which of the following is a reason that all large astronomical telescopes are reflecting telescopes? Choose one or more: A. Reflecting telescopes can be designed to be shorter than refracting telescopes. B. Reflecting telescopes minimize chromatic aberration. C. Reflecting telescopes are not as heavy as refracting telescopes. D. A reflecting telescope's glass doesn't need to be curved.

a, b, c

Based on the above graph, which of these types of light from astronomical sources are not observable from the ground? Choose one or more: A. gamma ray B. X-ray C. ultraviolet at 100 nm D. infrared at 1 micrometer (10-6 m) E. infrared at 100 micrometer (10-4 m) F. radio at 1 meter G. visible

a, b, c, e

In order for an electron to jump up two energy levels in an atom at once, it requires Choose one or more: A. a bluer photon than to jump up one energy level. B. any amount of energy. C. more energy than to jump up one energy level. D. a precise amount of energy.

a, c, d

Which of the following can astronomers determine from the spectrum of an object? Choose one or more: A. temperature B. mass C. speed toward or away from an observer D. composition E. diameter

a, c, d

Why is the Hubble Space Telescope in space instead of on the ground? Choose one or more: A. It observes in the UV. B. It has higher angular resolution. C. It's closer to things it's observing. D. It avoids atmospheric distortion.

a, d

As a blackbody becomes hotter, it also becomes __________ and __________. Choose one: A. less luminous; redder B. more luminous; bluer C. less luminous; bluer D. more luminous; redder

b

As wavelength increases, the energy of a photon __________ and its frequency __________. Choose one: A. increases; decreases B. decreases; decreases C. increases; increases D. decreases; increases

b

Besides adding adaptive optics to a telescope, what else can be done to reduce the effects of seeing? Choose one: A. Increase the integration time. B. Put the telescope at a higher altitude (the height above sea level). C. Build a larger telescope. D. Use a reflecting telescope instead of a refracting telescope.

b

Compared to your mass on Earth, on the Moon your mass would be Choose one: A. lower because the Moon is smaller than Earth. B. the same; mass doesn't change. C. higher because of the combination of the Moon's mass and size. D. lower because the Moon has less mass than Earth.

b

Given your results, what is the likely cause of Kepler's observation that planets travel faster when they are closer to the Sun? Choose one: A. The mass of the planet is greater when it is closer to the Sun. B. The force of gravity is stronger closer to the Sun. C. The force of gravity is weaker closer to the Sun. D. The mass of the Sun is greater when a planet is closer to it.

b

How might you improve your chances of detecting the motion of light if it moves at finite speed? Choose one: A. increase the brightness of the light source B. move farther away from the light source C. change the color of the light source D. move closer to the light source

b

If these tidal forces naturally cause synchronous rotation for each object, why is the Moon currently in synchronous rotation with the Earth, but the Earth is not in synchronous rotation with the Moon? Choose one: A. The precession of Earth's axis prevents the bulge from aligning with the Moon. B. The Moon is much less massive than the Earth, so it will take longer for it to slow the Earth into synchronous rotation. C. The Sun's gravity pulls in the opposite direction, speeding up Earth's rotation. D. Tidal forces must not be the cause—the Moon was coincidently in synchronous rotation with the Earth when it formed.

b

What causes the Moon to always keep the same face toward Earth? Choose one: A. tidal forces from the Sun B. tidal locking C. tidal forces from Earth D. tidal forces from the Earth and Sun

b

Why is an iron atom a different element from a sodium atom? Choose one: A. All possible answers are correct. B. An iron atom has more protons in its nucleus than a sodium atom. C. A sodium atom is bigger than an iron atom. D. A sodium atom has fewer neutrons in its nucleus than an iron atom.

b

You are shopping for telescopes online. You find two in your price range. One of these has an aperture of 20 cm, and one has an aperture of 30 cm. Which should you choose, and why? Choose one: A. The 20 cm, because the image size will be larger. B. The 30 cm, because the light-gathering power will be better. C. The 20 cm, because the light-gathering power will be better. D. The 30 cm, because the image size will be larger.

b

which of the following are implications of the finite speed of light? Choose one or more: A. Some rear-ending automobile accidents may have occurred because of the delay in the time it took for the light from the leading car to reach the following driver's eyes. B. There would be a noticeable delay in communications at the speed of light between Earth and astronauts on the Moon. C. Using a stopwatch precise to 1/10th of a second, the speed of light can be measured by an observer at the bottom of Mount Everest watching a light source at the top of Mount Everest. D. At the speed of light, it would take several months to travel to the nearest star. E. When we gaze at the Andromeda Galaxy, we are looking back in time to the way it used to appear millions of years ago. F. If the light of the Sun were suddenly extinguished, we wouldn't notice it from Earth for over 8 minutes.

b, e, f

An object in a(n) __________ orbit in the Solar System will remain in its orbit forever. An object in a(n) __________ orbit will escape from the Solar System. Choose one: A. unbound; bound B. circular; elliptical C. bound; unbound D. elliptical; circular

c

Astronauts in a space shuttle can float while orbiting Earth. Why are these astronauts weightless? Choose one: A. They are affected equally by the Moon's gravity and Earth's gravity. B. Everything in the orbiting shuttle is shielded from Earth's gravity. C. They are falling around Earth at the same rate as the shuttle. D. They and the space shuttle have escaped from Earth's gravity.

c

CCD cameras have much higher quantum efficiency than other detectors. As a result, CCD cameras can Choose one: A. split light into different colors. B. collect photons of different energies. C. generate a signal from fewer photons. D. collect photons for longer times.

c

Cameras that use adaptive optics provide higher spatial-resolution images primarily because Choose one: A. they simulate a much larger telescope. B. composite lenses correct for chromatic aberration. C. deformable mirrors are used to correct the blurring due to Earth's atmosphere. D. they operate above Earth's atmosphere.

c

Given the sense of rotation in the figure, and the location of the Earth's bulge with respect to the Moon, what effect would you expect to come from this reaction force? Choose one: A. The Earth's year will become shorter with time B. There will be no effect on the Earth from this force. C. The Earth's day will become longer with time. D. The Earth's day will become shorter with time. E. The Earth's year will become longer with time.

c

Imagine that you observe a star-planet system, edge-on. When the planet is moving away from Earth, in which direction is the star moving? Choose one: A. away from Earth B. across our line of sight, closer than the planet C. toward Earth D. across our line of sight, farther than the planet

c

Isaac Newton developed a theory of gravity by first considering Galileo's experiment of dropping objects of different masses from the Leaning Tower of Pisa. Galileo found that, when air resistance is negligible, all objects took the same amount of time to hit the ground when dropped from the top of the tower. choose the answer that best describes what Galileo's experiment implies. Choose one: A. The acceleration of objects dropped from the tower depends on their mass. B. The velocity of all objects dropped from the tower is constant with time. C. The acceleration of all objects dropped from the tower is the same. D. The inertia of all of the objects dropped from the tower is the same.

c

Newton's third law says that for every force there is an equal reaction force in the opposite direction. What does this imply about the force of gravity associated with a person standing on the Earth? Choose one: A. The force of gravity on the person cancels out to zero. B. There is twice as much gravitational force on the person than there would be if it weren't for Newton's third law. C. The Earth's gravity pulls downward on the person, and the person's gravity pulls upward on the Earth. D. The Earth's gravity pulls downward on the person but also pushes upward on them.

c

Subsequent semi-diurnal (twice daily) tides happen precisely once every 12 hours and 25 minutes. Given what you know of the motions of the Earth and Moon, where is this extra 25 minutes likely coming from? Choose one: A. the orbit of the Earth around the Sun B. the rotation of the Earth around its axis C. the orbit of the Moon around the Earth D. the rotation of the Moon around its axis

c

The "square" in the inverse square law comes from the fact that Choose one: A. distance increases like the radius of a sphere. B. volume increases like the radius of a sphere multiplied by itself twice (r × r × r). C. surface area increases like the radius of a sphere multiplied by itself.

c

The gravity of this off-center bulge has an effect on the Moon. Study the above figure, and choose the statement below that follows from it. Choose one: A. The Moon takes less time to orbit around the Sun as time passes. B. The Moon takes longer to orbit around the Sun as time passes. C. The Moon used to be closer to Earth than it is now. D. The Moon used to be farther from Earth than it is now.

c

Why do astronomers want to build the European Extremely Large Telescope (E-ELT) at this particular location in Chile? Choose one: A. This location is low in a valley, and the valley walls protect it from storms. B. This location is on public land, so it was inexpensive to purchase. C. This location is dry and cloudless almost all year. D. This location is always windy, which keeps dust, birds, and bugs away from the telescope.

c

Which of the following is the biggest disadvantage of putting a telescope in space? Choose one: A. Astronomers have to wait until the telescope comes back to Earth to get its images. B. Astronomers don't have as much control in choosing what to observe. C. Space telescopes can only observe in certain parts of the electromagnetic spectrum. D. Space telescopes are much more expensive than similar ground-based telescopes.

d

Choose all of the effects that would automatically happen if the wavelength of light were increased. Choose one or more: A. The energy of the light would increase. B. The speed of the light would increase. C. The amplitude of the wave would increase. D. The amplitude of the wave would decrease. E. The energy of the light would decrease. F. The frequency of the light would increase. G. The frequency of the light would decrease. H. The speed of the light would decrease.

e, g

match each telescope component with its ocular equivalent. (see ch 6 q1) 1. aperture 2. ccd 3. wiring to computer 4. objective lens

pupil = aperture retina = ccd optic =wiring to computer lens = objective lens iris = n/a