Astrophysics

19 Questions | Total Attempts: 457

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Astrophysics Quizzes & Trivia

Well.


Questions and Answers
  • 1. 
    What is an asteroid?
    • A. 

      A very large collection of stars.

    • B. 

      A stone.

    • C. 

      A mixture of rock and ice orbiting the sun.

    • D. 

      A small, minor planet that drifts in the solar system.

  • 2. 
    Why is the sun in equilibrium?
  • 3. 
    What is the luminosity of a star?
    • A. 

      The work done per unit time

    • B. 

      The energy emitted by unit time

    • C. 

      The energy it emits a year

    • D. 

      The brightness divided per area

  • 4. 
    What is the correct formula for apparent brightness?
    • A. 
    • B. 
    • C. 
  • 5. 
    Which of the following statements are correct if stars are moving towards us?
    • A. 

      Their wavelengths appear shorter

    • B. 

      The light waves reaching us are more spaced out

    • C. 

      The absorption lines appear blue-shifted

    • D. 

      The absorption lines appear red-shifted

  • 6. 
    Binary stars can always be seen with the naked eye.
    • A. 

      True

    • B. 

      False

  • 7. 
    What can a stellar spectra be used for?
  • 8. 
    What is a stellar parallax?
  • 9. 
    What is true for the apparent magnitude?
    • A. 

      Its symbol is little m

    • B. 

      It's a celestial body's apparent brightness when viewed by an observer on Earth

    • C. 

      It depends on luminosity and the distance of the star

    • D. 

      It has the unit parcel (pc)

    • E. 

      It has the unit light year (ly)

  • 10. 
    From the spectral class O to M:
    • A. 

      The temperature increases

    • B. 

      The temperature decreases

    • C. 

      The temperature stays the same

  • 11. 
    Absolute magnitude is the apparent magnitude viewed 15 pc from Earth.
    • A. 

      True

    • B. 

      False

  • 12. 
    A star of known luminosity is called
    • A. 

      A standard candle

    • B. 

      A spectroscopic parallax

    • C. 

      A cepheid

  • 13. 
    What is true for a cepheid?
    • A. 

      Its luminosity varies exponentially with time

    • B. 

      Its luminosity varies periodically with time

    • C. 

      The outer layers of the star undergoes periodic expansion anf contraction

    • D. 

      Due to the ionization of nitrogen there are variations in surface area and temperature

  • 14. 
    Spectroscopic parallax can be used to find the distance of a star, no matter how far away it is.
    • A. 

      True

    • B. 

      False

  • 15. 
    What is the critical density?
  • 16. 
    What is the mass density?