Fall 2000 ASTR 1120-001 Quiz 1

Choose the best answer and enter it on your scantron form. Be sure to fill in the boxes with your student number.

1. Which of the following is not a measure of distance:
   (a) meter; (b) Astronomical Unit; (c) parsec; (d) lightyear; (e) gigayear.

2. Sirius (a Canis Major), the brightest star in the sky bar the Sun, is 9 lightyears distant. As you gaze at it, you are seeing it:
   (a) as it will be in 18 years time; (b) as it will be in 9 years time; (c) as it is right now; (d) as it was 9 years ago; (e) as it was 18 years ago.

3. In 1673, Giovanni Cassini was able to obtain the first successful estimate of the Astronomical Unit (the Earth-Sun distance) by:
   (a) measuring the parallax of Mars; (b) showing that light produces interference patterns; (c) measuring the speed of light; (d) discovering the Galilean moons of Jupiter; (e) launching a hot air balloon.

4. The first successful measurement of a distance to a star other than the Sun was in 1838 by Friedrich Bessel, who measured the parallax of 61 Cyg to be 0.31 arcseconds, implying a distance of 3.2 parsecs. The crucial development that enabled this discovery was:
   (a) people got smarter; (b) telescopes capable of resolving better than 1 arcsecond, more than 60 times finer than the human eye; (c) the Earth was discovered to be round, not flat; (d) calculus; (e) light was discovered to be a wave.

5. The gravitational escape velocity from the surface of the Moon is 2 km/s. This means that:
   (a) the speed of sound on the Moon is 2 km/s; (b) the speed of light on the Moon is 2 km/s; (c) the Moon orbits the Earth at 2 km/s; (d) if, standing on the Moon, you threw a baseball at less than 2 km/s, it would fall back to the surface of the Moon; (e) it is colder on the Moon than on Earth.

6. Present day scientists refer to quanta of light as:
   (a) atoms; (b) corpuscles; (c) electrons; (d) gamma rays; (e) photons.

7. Compared to low energy light, high energy light has:
   (a) longer wavelength; (b) higher frequency; (c) higher velocity; (d) higher color; (e) more waves.

8. The difference between the green light and the blue light in a rainbow is:
   (a) the green light has more yellow light in it; (b) the green light is not as pure as the blue light; (c) the green light has a different wavelength; (d) the green light is hotter than the blue light; (e) green is not a color of the rainbow.

9. What kind of electromagnetic radiation can you hear with your ears:
   (a) radio waves; (b) microwaves; (c) infrared; (d) ultraviolet; (e) none?

10. An atom absorbs light:
    (a) at all wavelengths; (b) at random wavelengths; (c) at all wavelengths other than those at which it emits; (d) at certain characteristic wavelengths, the same wavelengths at which it emits; (e) more than it emits.