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2. Question 1
Modern telescopes use mirrors rather than lenses for all of these reasons EXCEPT
light passing through lenses can be absorbed or scattered.
large lenses can be very heavy.
large lenses are more difficult to make.
mirrors can be computer controlled to improve resolution.
reflecting telescopes aren’t affected by the atmosphere as much.
Answer: e
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3. Question 1
Modern telescopes use mirrors rather than lenses for all of these reasons EXCEPT
light passing through lenses can be absorbed or scattered.
large lenses can be very heavy.
large lenses are more difficult to make.
mirrors can be computer controlled to improve resolution.
reflecting telescopes aren’t affected by the atmosphere as much.
Explanation: Reflecting instruments like the KECK telescope can be made larger, and more effective, than refractors.
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4. Question 2 Seeing in astronomy is a measurement of the
quality of the telescope’s optics.
transparency of a telescope’s lens.
sharpness of vision of your eyes.
image quality due to air stability.
sky’s clarity and absence of clouds.
Answer: d
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5. Question 2 Seeing in astronomy is a measurement of the
quality of the telescope’s optics.
transparency of a telescope’s lens.
sharpness of vision of your eyes.
image quality due to air stability.
sky’s clarity and absence of clouds.
Explanation: “Good seeing” occurs when the atmosphere is clear and the air is still. Turbulent air produces “poor seeing, and fuzzier images.
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6. Question 3 Diffraction is the tendency of light to
bend around corners and edges.
separate into its component colors.
bend through a lens.
disperse within a prism.
reflect off a mirror.
Answer: a
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7. Question 3 Diffraction is the tendency of light to
bend around corners and edges.
separate into its component colors.
bend through a lens.
disperse within a prism.
reflect off a mirror.
Explanation: Diffraction affects all telescopes and limits the sharpness of all images.
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8. Question 4 Resolution is improved by using
larger telescopes and longer wavelengths.
infrared light.
larger telescopes and shorter wavelengths.
lower frequency light.
visible light.
Answer: c
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9. Question 4 Resolution is improved by using
larger telescopes and longer wavelengths.
infrared light.
larger telescopes and shorter wavelengths.
lower frequency light.
visible light.
Explanation: Diffraction limits resolution; larger telescopes and shorter wave light produces sharper images.
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10. Question 5
An advantage of charge-coupled devices (CCDs) over photographic film is that
they don’t require chemical development.
digital data are easily stored and transmitted.
CCDs are more light sensitive than film.
CCD images can be developed faster.
all of the above are true.
Answer: e
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11. Question 5
An advantage of charge-coupled devices (CCDs) over photographic film is that
they don’t require chemical development.
digital data are easily stored and transmitted.
CCDs are more light sensitive than film.
CCD images can be developed faster.
all of the above are true.
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12. Question 6 Radio dishes are large in order to
improve angular resolution.
give greater magnification.
increase the range of waves they can collect.
detect shorter waves than optical telescopes for superior resolution.
Answer: a
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13. Question 6 Radio dishes are large in order to
improve angular resolution.
give greater magnification.
increase the range of waves they can collect.
detect shorter waves than optical telescopes for superior resolution.
Explanation: Resolution is worse with long-wave light, so radio telescopes must be large to compensate.
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14. Question 7 Adaptive optics refers to
making telescopes larger or smaller.
reducing atmospheric blurring using computer control.
collecting different kinds of light with one type of telescope.
using multiple linked telescopes.
Answer: b
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15. Question 7 Adaptive optics refers to
making telescopes larger or smaller.
reducing atmospheric blurring using computer control.
collecting different kinds of light with one type of telescope.
using multiple linked telescopes.
Explanation: Shaping a mirror in real time can dramatically improve resolution.
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16. Question 8 Radio telescopes are useful because
observations can be made day and night.
we can see objects that don’t emit visible light.
radio waves are not blocked by interstellar dust.
they can be linked to form interferometers.
all of the above are true.
Answer: e
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17. Question 8 Radio telescopes are useful because
observations can be made day and night.
we can see objects that don’t emit visible light.
radio waves are not blocked by interstellar dust.
they can be linked to form interferometers.
all of the above are true.
Explanation: The Very Large Array links separate radio telescopes to create much better resolution.
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18. Question 9 Infrared telescopes are very useful for observing
pulsars and black holes.
from locations on the ground.
hot stars and intergalactic gas.
neutron stars.
cool stars and star-forming regions.
Answer: e
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19. Question 9 Infrared telescopes are very useful for observing
pulsars and black holes.
from locations on the ground.
hot stars and intergalactic gas.
neutron stars.
cool stars and star-forming regions.
Explanation: Infrared images of star-forming “nurseries” can reveal objects still shrouded in cocoons of gas and dust.
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20. Question 10
The Hubble Space Telescope (HST) offers sharper images than ground telescopes primarily because
HST is closer to planets and stars.
HST uses a larger primary mirror.
it gathers X-ray light.
HST orbits above the atmosphere.
it stays on the nighttime side of Earth.
Answer: d
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21. Question 10
The Hubble Space Telescope (HST) offers sharper images than ground telescopes primarily because
HST is closer to planets and stars.
HST uses a larger primary mirror.
it gathers X-ray light.
HST orbits above the atmosphere.
it stays on the nighttime side of Earth.
Explanation: HST orbits less than 400 miles above Earth—not much closer to stars and planets! But it can gather UV, visible, and infrared light, unaffected by Earth’s atmosphere.
© 2017 Pearson Education, Inc.