ASTR 1020 SPRING 2012: QUIZ #2

VERSION C

Please put away all electronic devices. You will not need a calculator for this quiz.

SELECT THE BEST ANSWER TO EACH PROBLEM.

1. Newton's Second Law of Motion tells us that the net force applied to an object equals its:
a) mass times energy.
b) momentum times velocity.
c) mass times velocity.
d) energy times acceleration.
e) mass times acceleration.

e) mass times acceleration.

2. Which of the following stars is luminosity class I?
a) The Sun.
b) Sirius B.
c) Proxima Centaurus.
d) Alpha Centaurus A.
e) Betelgeuse.

e) Betelgeuse.

3. Which of the following spectral types of stars has the strongest Titanium Oxide lines?
a) A.
b) B.
c) G.
d) M.
e) O.

d) M.

4. A fifth magnitude star is:
a) 2.5 times fainter than a sixth magnitude star.
b) 2.5 times brighter than a sixth magnitude star.
c) 100 times fainter than a sixth magnitude star.
d) 100 times brighter than a sixth magnitude star.
e) 5 times brighter than a sixth magnitude star.

b) 2.5 times brighter than a sixth magnitude star.

5. Individual sunspots typically last about:
a) 5-10 minutes.
b) 1 - 100 days.
c) 6 months.
d) 11 years.
e) 26,000 years.

b) 1 - 100 days.

6. True physical motion of a star through space perpendicular to our line of sight is called:
a) Rapid Walk motion.
b) Stellar parallax.
c) Proper motion.
d) Doppler shift.
e) Spectroscopic parallax.

c) Proper motion.

7. If the distance between the Earth and the Moon decreased to 1/4 its current distance, how would the gravitational force on the Earth due to the Moon change?
a) It would increase by a factor of 4.
b) It would decrease by a factor of 4.
c) It would increase by a factor of 16.
d) It would decrease by a factor of 16.
e) It would stay the same.

c) It would increase by a factor of 16.

8. Which of the following is true about the corona of the Sun?
a) it is visible during an annular eclipse.
b) it is hotter than the photosphere.
c) it contains higher density gas than the photosphere.
d) it lies between the core of the Sun and the convective zone.
e) nuclear fusion occurs within the corona of the Sun.

b) it is hotter than the photosphere.

9. Sometimes large loops of gas are seen extending up from the photosphere of the Sun, connecting neighboring sunspots. These arcs of gas are called:
a) solar flares.
b) granules.
c) spicules.
d) dynamos.
e) prominences.

e) prominences.

10. Ball A has a mass of two kilograms. Ball B has a mass of four kilograms. They are hit with a bat with the same force.
a) The subsequent acceleration of Ball A is half as much as that of Ball B.
b) The subsequent acceleration of Ball A is twice as much as that of Ball B.
c) The subsequent acceleration of Ball A is four times that of Ball B.
d) The subsequent acceleration of Ball A is the same as that of Ball B.
e) The velocity of Ball A and Ball B does not change.

b) The subsequent acceleration of Ball A is twice as much as that of Ball B.

11. If the mass of the Earth suddenly tripled, how would the gravitational force between the Earth and the Moon change?
a) it would increase by a factor of nine.
b) it would increase by a factor of three.
c) it would decrease by a factor of three.
d) it would decrease by a factor of nine.
e) it would stay the same.

b) it would increase by a factor of three.

12. The temperature of the photosphere of a G star is:
a) Lower than that of an B star, but higher than an K star.
b) Higher than that of an B star, but lower than an K star.
c) Higher than those of both B and K stars.
d) Lower than those of both B and K stars.
e) It depends upon the luminosity; some G stars have very large photospheric temperatures; others have very low temperatures.

a) Lower than that of an B star, but higher than an K star.

13. What is Cecilia Payne-Gaposchkin best known for?
a) Being the first person to create a plot of luminosity vs. temperature for stars.
b) Re-organizing the spectral sequence ABCDEF... to the sequence used today.
c) Determining that the acceleration of an object is inversely proportional to its mass.
d) Determining that the gravitational force between two objects is inversely proportional to the square of the distance apart.
e) Determining that stars are made up of mostly hydrogen and helium.

e) Determining that stars are made up of mostly hydrogen and helium.

14. Inertia is:
a) the gravitational force on an object.
b) a change in velocity with time.
c) a change in speed with time.
d) the tendency of objects to resist changes in motion.
e) the true motion of an object in the plane of the sky.

d) the tendency of objects to resist changes in motion.

15. Which of the following has a temperature of about 6000K?
a) The core of the Sun.
b) The photosphere of an MI star.
c) The photosphere of a G2 star.
d) The photosphere of an OV star.
e) The photosphere of an MV star.

c) The photosphere of a G2 star.

16. Newton's first Law of Motion can be paraphrased as:
a) F = MA
b) F1 = F2
c) objects in motion with no forces acting on them tend to slow down and stop.
d) objects in motion keep moving with constant velocity unless acted upon by a force.
e) F = G M1M2/R2.

d) objects in motion keep moving with constant velocity unless acted upon by a force.

17. Which of the following spectral types of stars has the lowest photospheric temperature?
a) A.
b) B.
c) G.
d) M.
e) O.

d) M.

18. The Sun has a mass 1000 times larger than the mass of Jupiter. Therefore the acceleration of the Sun due to Jupiter is:
a) 1000 times larger than the acceleration of Jupiter due to the Sun.
b) 10002 = 1,000,000 times larger than the acceleration of Jupiter due to the Sun.
c) the same as the acceleration of Jupiter due to the Sun.
d) 1/1000th of the acceleration of Jupiter due to the Sun.
e) 1/10002 = 1/1,000,000 of the acceleration of Jupiter due to the Sun.

d) 1/1000th of the acceleration of Jupiter due to the Sun.

19. A period of 11 years is:
a) Approximately the lifetime of a sunspot.
b) Approximately the lifetime of a granule on the Sun's surface.
c) Approximately the time it takes the Sun to rotate once.
d) Approximately how often the overall magnetic polarity of the Sun flips.
e) Approximately how often the overall magnetic polarity of the Earth flips.

d) Approximately how often the overall magnetic polarity of the Sun flips.

20. Which of the following spectral types of stars has the strongest hydrogen absorption lines (H-alpha, H-beta, and H-gamma)?
a) A.
b) B.
c) G.
d) M.
e) O.

a) A.