Astro 001 Exam 4 UPDATED Study
ACTUAL QUESTIONS AND CORRECT
ANSWERS
An up quark has charge +2/3, a down quark has charge -1/3, and a strange quark
has charge -1/3. The Sigma+ particle is formed by a combination of two up quarks
and one strange quark. What is its charge?
A) 1
B) -1/3
C) -1
D) +1/3
E) 0 - CORRECT ANSWER A) 1
Which source generates the most energy over its lifetime?
A) A supernova.
B) The Sun.
C) A camp fire.
D) A quasar.
E) A gamma-ray burst. - CORRECT ANSWER D) A quasar
What is the role of collisions between galaxies in the formation and evolution of galaxies
A) galaxies are much too far apart to ever have collisions
B) in a collision both galaxies are always destroyed so galaxy formation must be an ongoing
process
C) galaxies are moving very fast and when they collide they always just move right through
each other, never to interact again
D) in a collision all the stars in the galaxies are spread out and then must find other stars and
come together and form new galaxies
E) larger galaxies may have formed from the merger of smaller ones - CORRECT
ANSWER E) larger galaxies may have formed from the merger of smaller ones
, Which have more massive supermassive black holes, spiral galaxies like Andromeda or
elliptical galaxies like Cygnus A?
A) Ellipticals.
B) Neither type of galaxies has supermassiave black holes.
C) Both are the same.
D) Spirals.
E) Supermassive black holes do not exist at all. - CORRECT ANSWER A) Ellipticals
What category do astronomers use if a galaxy does not fit into the spiral or elliptical
category?
A) Primordial.
B) Funny.
C) Giant.
D) Dwarf.
E) Irregular. - CORRECT ANSWER E) Irregular
Which is true about cold dark matter?
A) Cold dark matter interacts strongly with ordinary baryonic matter via the strong force.
B) Cold dark matter particles travel faster than the speed of light.
C) Cold dark matter exists only within planets and stars but not in other parts of galaxies or
intergalactic space.
D) Cold dark matter emits X-rays, but no other forms of radiation.
E) Cold dark matter particles travel more slowly than hot dark matter particles. - CORRECT
ANSWER E) Cold dark matter particles travel more slowly than hot dark matter
particles
How do astronomers measure the mass of a supermassive black hole?
A) by comparing its X-ray luminosity to its radio luminosity
B) by measuring its parallax
ACTUAL QUESTIONS AND CORRECT
ANSWERS
An up quark has charge +2/3, a down quark has charge -1/3, and a strange quark
has charge -1/3. The Sigma+ particle is formed by a combination of two up quarks
and one strange quark. What is its charge?
A) 1
B) -1/3
C) -1
D) +1/3
E) 0 - CORRECT ANSWER A) 1
Which source generates the most energy over its lifetime?
A) A supernova.
B) The Sun.
C) A camp fire.
D) A quasar.
E) A gamma-ray burst. - CORRECT ANSWER D) A quasar
What is the role of collisions between galaxies in the formation and evolution of galaxies
A) galaxies are much too far apart to ever have collisions
B) in a collision both galaxies are always destroyed so galaxy formation must be an ongoing
process
C) galaxies are moving very fast and when they collide they always just move right through
each other, never to interact again
D) in a collision all the stars in the galaxies are spread out and then must find other stars and
come together and form new galaxies
E) larger galaxies may have formed from the merger of smaller ones - CORRECT
ANSWER E) larger galaxies may have formed from the merger of smaller ones
, Which have more massive supermassive black holes, spiral galaxies like Andromeda or
elliptical galaxies like Cygnus A?
A) Ellipticals.
B) Neither type of galaxies has supermassiave black holes.
C) Both are the same.
D) Spirals.
E) Supermassive black holes do not exist at all. - CORRECT ANSWER A) Ellipticals
What category do astronomers use if a galaxy does not fit into the spiral or elliptical
category?
A) Primordial.
B) Funny.
C) Giant.
D) Dwarf.
E) Irregular. - CORRECT ANSWER E) Irregular
Which is true about cold dark matter?
A) Cold dark matter interacts strongly with ordinary baryonic matter via the strong force.
B) Cold dark matter particles travel faster than the speed of light.
C) Cold dark matter exists only within planets and stars but not in other parts of galaxies or
intergalactic space.
D) Cold dark matter emits X-rays, but no other forms of radiation.
E) Cold dark matter particles travel more slowly than hot dark matter particles. - CORRECT
ANSWER E) Cold dark matter particles travel more slowly than hot dark matter
particles
How do astronomers measure the mass of a supermassive black hole?
A) by comparing its X-ray luminosity to its radio luminosity
B) by measuring its parallax
