Astronomy Test #1 (Ch. 0,1,2,and 3)

Card Set Information

Author:
Anonymous
ID:
284695
Filename:
Astronomy Test #1 (Ch. 0,1,2,and 3)
Updated:
2014-10-02 07:49:08
Tags:
Astronomy
Folders:

Description:
Astronomy Test #1, Prof. Birjoo Vashinav
Show Answers:

Home > Flashcards > Print Preview

The flashcards below were created by user Anonymous on FreezingBlue Flashcards. What would you like to do?


  1. Chapter 3: Question 31
    What problem do refractor telescopes have that reflectors don't?
    A. bad seeing
    B. atmospheric blurring
    C. chromatic aberration
    D. light loss from secondary elements
    E. diffraction limited resolution
    • C. Chromatic Aberration
    • Chromatic Aberration: when light is separated into its component colors
    • Diffraction Limited Resolution: for light, of any given wavelength, large telescopes produce less diffraction than small ones
  2. Chapter 3: Question 30
    Which of the following is NOT a reason to use a reflecting telescope rather than a refractor?
    A.Heavy lenses, which can only be supported at their edges, tend to deform under their own weight. 
    B.Lenses absorb light, while mirrors do not.
    C.Lenses are harder to focus than mirrors.
    D.Lenses are subject to chromatic aberration.
    E.A lens must have two precision surfaces; a mirror needs only one.
    C
  3. Chapter 3: Question 11
    The light-gathering ability of a telescope is most dependent on the diameter of its primary objective. True or False?
    True
  4. Chapter 3: Question 13
    A telescope with an 8-inch mirror will collect twice as much light as one with a 4-inch mirror.
    True or False?
    False
  5. Chapter 3: Question 14
    The 400" Keck reflector can see objects 100 times fainter than the 40" Yerkes lens. True or False?
    True
  6. Chapter 3: Question 15
    Radio telescopes have poorer angular resolution than optical telescopes because radio waves have a much longer wavelength than optical waves. True or False?
    True
  7. Chapter 3: Question 39
    What is the resolution of a telescope?
    A.its ability to see very faint objects its ability to separate light into its component colors for analysis
    B.its ability to make distant objects appear much closer to us
    C.its ability to focus more than just visible light for imaging
    D.its ability to distinguish two adjacent objects close together in the sky
    D
  8. Chapter 3: Question 42
    Green light has a shorter wavelength than orange light. In a 5 inch telescope, green light will...
    A.reduce the effects of atmospheric turbulence.
    B.provide worse angular resolution than orange light.
    C.come to the same exact focus as orange light.
    D.provide better angular resolution than orange light.
    E.allow dimmer stars to be observed.
    D
  9. Chapter 3: Question 18
    The opacity of the atmosphere is partially corrected via adaptive optics. True or False?
    False
  10. Chapter 3: Question 43
    What problem does adaptive optics correct?
    A.chromatic aberration due to use of only a single lens objective
    B.the light pollution of urban areas
    C.turbulence in the Earth's atmosphere that creates twinkling
    D.defects in the optics of the telescope, such as the original Hubble mirror
    E.the opacity of the Earth's atmosphere to some wavelengths of light
    C.
    (this multiple choice question has been scrambled)
  11. Reflecting Telescopes characterisitics and examples:
    • -World's largest telescope
    • -Most commonly used by professionals astronomers today
    • -Ex: The Hubble Space Telescope
  12. Refracting Telescopes characteristics and examples:
    • -Incoming light passes through glass
    • -Very large telescopes become "top-heavy"
    • -The world's largest is 1-meter in diameter
    • -Ex: Galileo's Telescopes
  13. Chapter 3: Question 20
    Optical telescopes are usually used only at night, but radio telescopes can be used day or night. True or False?
    True
  14. Chapter 3: Question 21
    The Earth's atmosphere is the major factor limiting the use of ground-based radio telescopes. True or False?
    False
  15. Chapter 3: Question 22
    Optical interferometry is more in use than radio interferometry. True or False?
    False
  16. Chapter 3: Question 44
    What is true of radio telescopes?
    A.They are most sensitive to the opacity of the ozone layer.
    B.They have better angular resolution than a reflector.
    C.They are the smallest, most compact telescopes.
    D.They have poorer angular resolution than a refractor of the same size.
    E.They can only be used above the atmosphere.
    D
  17. Chapter 3: Question 46
    In astronomy, an interferometer can be used to...
    A.improve the angular resolution of radio telescopes.
    B.increase the sensitivity of infrared telescopes to longer wavelengths.
    C.decrease the effects of light pollution in getting darker sky backgrounds.
    D.yield better seeing conditions with optical telescopes.
    E.speed up the processing of CCD images.
    A
  18. Chapter 3: Question 28
    Galaxies look the same whether viewed in visible or X-ray wavelengths. True or False?
    False
  19. Chapter 3: Question 27
    The Compton GRO was the first telescope used for our exploration of high-energy astronomy. True or False?
    False
  20. Chapter 3: Question 26
    The mirrors for X-ray telescopes are the same shape as those of optical reflectors. True or False?
    False
  21. Chapter 3: Question 25
    Due to our ozone layer, ultraviolet astronomy must be done from space. True or False?
    True
  22. Chapter 3: Question 24
    Like radio and optical astronomy, infrared astronomy is easily done with ground-based telescopes. True or False?
    False
  23. Chapter 3: Prelecture Question 14
    Which of the following regions of the elctromagnetic spectrum is useful for studying distant galaxies?
    A.Radio waves
    B.Visible light
    C.Infrared light
    D.Ultraviolet light
    E.All of the above
    E
  24. Chapter 3: Question 50
    Which of the following is currently supplying high resolution X-ray images from space?
    A.Chandra
    B.HEAO-2
    C.COBE
    D.Einstein
    E.ROSAT
    A
  25. Conceptual Self-Test 3.02
    The term seeing is used to describe how faint an object can be detected by a telescope. True or False?
    False
  26. Conceptual Self-Test 3.03
    One of the primary advantages of CCDs over photographic plates is the former's high efficiency in detecting light. True or False?
    True
  27. Conceptual Self-Test 3.04
    Radio telescopes are large in part to improve their angular resolution, which is poor because of the long wavelengths at which they are used to observe the skies. True or False?
    True
  28. Conceptual Self-Test 3.05
    Infared astronomy can only be done from space. True or False?
    False
  29. Conceptual Self-Test 3.06
    Gamma-ray telescopes employ the same basic design that optical instruments use. True or False?
    False
  30. Conceptual Self-Test 3.07
    Because gamma rays have very short wavelengths, gamma-ray telescopes can achieve extremely high angular resolution. True or False?
    False
  31. Conceptual Self-Test 3.08
    The main reason that most professional research telescopes are reflectors is that...
    A.their images are inverted.
    B.they do not suffer from the effects of seeing.
    C.large mirrors are easier to build than large lenses.
    D.mirrors produce sharper images than lenses do.
    C
  32. Conceptual Self-Test 3.10
    The primary reason professional observatories are built on the highest mountaintops is to...
    A.improve chromatic aberration.
    B.reduce atmospheric blurring.
    C.be above the rain clouds.
    D.get away from city lights.
    B
  33. Conceptual Self-Test 3.11
    When multiple radio telescopes are used for interferometry, resolving power is most improved by...
    A.increasing the number of telescopes in a given area.
    B.the distance between telescopes.
    C.the diameter of each telescope.
    D.the electrical power supplied to each telescope.
    B
  34. Conceptual Self-Test 3.12
    The Spitzer Space Telescope (SST) is stationed far from Earth because...
    A.doing so avoids the obscuring effects of Earth's atmosphere.
    B.Earth is a heat source and the telescope must be kept very cool.
    C.this increases the telescope's field of view.
    D.the telescope is sensitive to electromagnetic interference from terrestrial radio stations
    B
  35. Conceptual Self-Test 3.13
    The best way to study young stars hidden behind interstellar dust clouds would be to use...
    A.X-rays.
    B.blue light.
    C.infrared light.
    D.ultraviolet light.
    C
  36. Conceptual Self-Test 3.14 VIS
    Resolution is sharpest when the ratio of wavelengths to telescope size is...
    A.Small
    B.close to 1
    C.large
    D.none of these
    A
  37. Conceptual Self-Test 3.15 VIS
    The best frequency wave in which to study the hot (million-kelvin) gas found among the galaxies in the Virgo cluster would be...
    A.in X rays.
    B.in gamma rays.
    C.at radio frequencies.
    D.in the infrared rays.
    A
  38. Chapter 1: Question 16
    In Ptolemy's geocentric model, retrograde motion occurs when the planet is closest to us, on the inside portion of...
    A.equant.
    B.ecliptic.
    C.deferent.
    D.ellipse.
    E.epicycle.
    E
  39. Chapter 1: Question 14
    In Ptolemy's geocentric model, the planet's motion along its deferent is all that is needed to understand retrograde motion. True or False?
    False
  40. Chapter 1: Question 22
    Which of these was NOT seen telescopically by Galileo?
    A.sunspots
    B.Four moons around Jupiter
    C.craters and mare on the Moon
    D.Venus' phase cycle
    E.stellar parallax
    E
  41. Chapter 1: Question 12
    Galileo's observations of the entire phase cycle of Venus proved that Ptolemy's epicycles could not be correct in keeping Venus between us and the Sun. True or False?
    True
  42. Vocabulary in Context: Kepler's Planetary Orbits
    1. Earth is located at one __ of the Moon's orbit.
    2. According to Kepler's second law, Jupiter will be traveling most slowly around the Sun when at __.
    3. Earth orbits in the shape of a/an __ around the Sun.
    4. The mathematical form of Kepler's third law measures the period in years and the __ in astronomical units (AU).
    5. According to Kepler's second law, Pluto will be traveling fastest around the Sun when at __.
    6. The extent to which Mars' orbit differs from a perfect circle is called its __.
    • 1.Focus
    • 2.Aphelion
    • 3.Ellipse
    • 4.Semi-major Axis
    • 5.Perihelion
    • 6.Eccentricity
    • -Aphelion: greatest distance from the Sun
    • -Perihelion: point of closest approach to the Sun
    • -Eccentricity: how far off an orbit is from an elliptical path
  43. Ranking Task: Kepler's Third Law of Planetary Motion
    1. Planets move fastest when they are at the __ (right side).
    2. Planets move slowest when they are at the __ (left side).
    3. Planetary Orbits go __.
    4. Does mass effect orbital periods?
    5. Kepler's Third Law formula is __.
    • 1. Aphelion
    • 2. Perihelion
    • 3. Counter-clockwise
    • 4. No
    • 5. P^2 (in Earth)=A^3 (in AU)
    • -P=orbital period
    • -A=Semimajor axis
  44. Ranking Task: Kepler's Second Law
    1. Kepler's second law states: an imaginary line connecting the Sun to any planet sweeps out __of the ellipse in __.
    2. When a planet is ___ to the Sun it moves ___ than when ___ away.
    3. When an object is __ to the Sun then, it covers ___ than when it was ___.
    • 1. equal areas/ equal intervals of time
    • 2. closest/faster/farther
    • 3. close/greater distance/farther away
  45. Chapter 1: Question 8
    Kepler found the orbits of planets are ellipses, not circles. True or False?
    True
  46. Chapter 1: Question 25
    Tycho Brahe's contribution to Kepler's Laws of Planetary Motion were...
    A.a precise lunar calendar.
    B.a mathematical explanation of epicycles.
    C.his detailed and accurate observations of the planets' positions.
    D.the correct explanation of lunar phases.
    E.his observations of Jupiter's moons.
    C
  47. Chapter 1: Question 3
    According to Newton's Second Law, if you double the force acting on a body, the acceleration will double. True or False?
    True

What would you like to do?

Home > Flashcards > Print Preview