Question

1) The missing mass problem is a) starlight is observed, but there is no evidence of...

1) The missing mass problem is

a) starlight is observed, but there is no evidence of mass
b) the amount of mass measured is less than the amount of light measured
c) starlight follows the same distribution as mass
d) there are indications of mass from motion but no light
e) spacetime is warped by mass

2) The rotation curve of the Galaxy is

a) flat in the core, planet-like in the disk
b) wheel-like in the core, flat in the disk
c) planet-like all over
d) wheel-like in the core, planet-like in the disk
e) planet-like in the core, wheel-like in the disk

3) Under gravity, the amount of mass goes as velocity squared (v2). If the velocity of one cluster is 4 times the velocity of another, then its mass is

a) 1/2 the other cluster
b) the same as the other cluster
c) twice the other clusters
d) 4 times the other clusters
e) 16 times the other clusters

4) The amount of dark matter is expressed as the ratio of mass to light (M/L). For the Sun, the mass is one solar mass and the luminosity is one solar luminosity for a M/L of 1. If a galaxy has 108 solar masses and 107 solar luminosities, then its M/L is

a) 1
b) 2
c) 10
d) 100
e) cannot determine from information given

5) If galaxy A has a M/L of 0.5, galaxy B has a M/L of 1 and galaxy C has a M/L of 10, which has more dark matter?

a) A
b) B
c) C
d) B and C have the same amount
e) A and C have the same amount

6) From this figure, we see that a M/L value needed to close the Universe is

a) 1
b) 10
c) 200
d) 900
e) 10,000

7) From the same figure, the scale of superclusters is

a) 1 kpc
b) 10 kpc
c) 1 Mpc
d) 20 Mpc
e) 2000 Mpc

8) Which of the following would be a poor baryonic dark matter candidate?

a) bowling balls
b) people
c) stars
d) neutrons
e) WIMPS

9) Distant supernova data indicates that

a) ? matter is 1
b) the Universe is less than 3 billion years old
c) the Universe is greater than 30 billion years old
d) the cosmological constant is zero
e) the Universe is accelerating

10) Using this figure, if the Universe is flat and the cosmological constant is less than zero, then

a) the Universe will expand forever
b) the Universe will accelerate
c) the Universe will collapse
d) the Universe will slow to zero velocity
e) cannot determine from information given

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Answer #1

1, b the amount of mass measured is less than the amount of light measured

2.d wheel-like in the core, planet-like in the disk

3.e) 16 times the other clusters

4.c) 10

5.c) C

6. where is the figure

7.where i th fig

8.d

9.b

10.no fig

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Answer #2

1) The missing mass problem is

b) the amount of mass measured is less than the amount of light measured

2) The rotation curve of the Galaxy is

a) flat in the core, planet-like in the disk

3) Under gravity, the amount of mass goes as velocity squared (v2). If the velocity of one cluster is 4 times the velocity of another, then its mass is


c) twice the other clusters

4) The amount of dark matter is expressed as the ratio of mass to light (M/L). For the Sun, the mass is one solar mass and the luminosity is one solar luminosity for a M/L of 1. If a galaxy has 108 solar masses and 107 solar luminosities, then its M/L is

M/L =10^8/10^7 =10


c) 10

5) If galaxy A has a M/L of 0.5, galaxy B has a M/L of 1 and galaxy C has a M/L of 10, which has more dark matter?

as M/L ratio represents amount of dark matter C has most dark matter


c) C

6) From this figure, we see that a M/L value needed to close the Universe is

no figure is give so could not answer questions 6 and 7

8) Which of the following would be a poor baryonic dark matter candidate?

in astronomy and cosmology, baryonic dark matter is dark matter composed of baryons, i.e. protons and neutrons and combinations of these.

where as WIMPS (Weakly interacting massive particles) are assumed to be mass and no interacting particles like proton and neutron hence answer is

d) WIMPS

9) Distant supernova data indicates that


e) the Universe is accelerating

10) Using this figure, if the Universe is flat and the cosmological constant is less than zero, then

cnnnot answer as given fig is not given but generally

a) the Universe will expand forever

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