1. Hydrogen has a proton in its nucleus Deuterium has a proton and a neutron in its nucleus. Hydrogen and deuterium are two ____ of the same _____.
   (A) elements, isotope
   (B) ions, element
   (C) isotopes, element
   (D) ions, isotope
   (E) peas, pod

2. Blackbody radiation depends on only temperature. If a blackbody is heated, it will become
   (A) bluer and dimmer.
   (B) bluer and brighter.
   (C) redder and dimmer.
   (D) redder and brighter.
   (E) don't know.

3. A blackbody produces what kind of spectrum?
   (A) continuous
   (B) emission line
   (C) absorption line
   (D) emission and absorption lines
   (E) none

4. A hot, low-density gas will produce what kind of spectrum?
   (A) continuous
   (B) emission line
   (C) absorption line
   (D) emission and absorption lines
   (E) none

5. A hot, high-density gas will produce what kind of spectrum?
   (A) continuous
   (B) emission line
   (C) absorption line
   (D) emission and absorption lines
   (E) none

6. A hot, high-density source viewed through a cooler, low-density gas will show
   (A) continuous spectrum without lines.
   (B) continuous spectrum with emission lines.
   (C) continuous spectrum with absorption lines.
   (D) emission-line spectrum
   (E) emission and absorption lines.

7. Stars emit blackbody radiation. If a star is surrounded by a layer of cool and low-density gas, this surrounding gas would
   (A) emit its own blackbody radiation.
   (B) produce emission lines over the stellar blackbody continuum.
   (C) produce absorption lines over the stellar blackbody continuum.
   (D) amplify the stellar blackbody radiation.
   (E) obscure the stellar blackbody radiation.

8. When an electron in an atom makes a transition from a high energy level to a lower energy level, it
   (A) emits a photon.
   (B) absorbes a photon.
   (C) stores the energy in the nucleus.
   (D) stores the energy in itself.
   (E) cannot happen.

9. Spectral lines have discrete wavelengths because
   (A) electrons can have arbitrary energies.
   (B) electrons can make transitions only between quantized energy levels.
   (C) electrons absorb photons to lower their energy levels.
   (D) electrons emit photons to reach higher energy levels.
   (E) all of the above.

10. The rainbow we see after a rainstorm is
    (A) an illusion.
    (B) the spectrum of the gold at its end.
    (C) the spectrum of the Sun.
    (D) the spectrum of water.
    (E) the spectrum of oxygen and nitrogen in the Earth's atmosphere.

11. We can determine the chemical compositions of a star by analyzing
    (A) the rock sample collected from the star.
    (B) the brightness of the star.
    (C) the continuous spectrum of the star.
    (D) the spectral lines in its spectrum.
    (E) all of the above.

12. The color of a star can be used to determine the star's
    (A) brightness.
    (B) temperature.
    (C) chemical composition.
    (D) age.
    (E) magnetic field.

13. When we call a telescope a "4m telescope", the "4m" refers to the telescope's
    (A) length
    (B) diameter
    (C) radius
    (D) focal length
    (E) none of the above

14. Telescopes are important tools for astronomers to collect light. The light-gathering power of a telescope is proportional to the aperture (surface area) of its mirror or lens; therefore, the light-collecting power of the Keck 10-m telescope is X times the power of the University of Illinois 1-m telescope.
    (A) 1/100
    (B) 1/10
    (C) 1
    (D) 10
    (E) 100

15. Optical telescopes use lens or mirror to collect light. The ones using lens are called "refractors". The size of a lens is usually limited because the glass in a lens is heavy. Therefore, the largest refractors are
    (A) 12-inch telescopes.
    (B) 1-m telescopes.
    (C) 4-m telescopes.
    (D) 10-m telescopes.
    (E) orbiting around the Earth.

16. Which of the following is recommended at a radio telescope?
    (A) speak softly so that astronomers can listen to the telescope
          (just be considerate)
    (B) plug an ear phone into a computer and listen to the signal
          (as Jodi Foster did in the movie Contact).
    (C) fill the Arecibo 1000-ft telescope with water
          (as done in the 007 movie Golden Eye).
    (D) wear a hard hat near a telescope
          (as Prof Chu did at the VLA and Arecibo)
    (E) all of above

17. Using a larger telescope, we can
    (A) get sharper images.
    (B) collect more light from an astronomical object.
    (C) observe fainter objects.
    (D) all of above

18. On a snowy night, astronomers can
    (A) use an optical telescope to take pictures of the sky.
    (B) use an optical telescope to take spectra of stars.
    (C) frolic in the snow and make snowmen.
    (D) observe with the Hubble Space Telescope.
    (E) C and D.

19. Gamma-ray, X-ray, and UV telescopes are usually on satellites orbiting around the Earth in space because
    (A) the Earth's atmosphere absorbs these energetic photons.
    (B) the telescopes are radioactive.
    (C) it is a tradition.
    (D) it is prestigious to carry NASA's logo on a telescope.
    (E) NASA wants to collect fees from astronomers.

20. The surface gravity on the Moon is 1/6 that on the Earth. This means that a person who weighs 180-lb on the Earth would weigh ____ on the Moon.
    (A) 30 lb.
    (B) 180 lb.
    (C) 1080 lb

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Last updated September 22, 2001

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