Ch. 11b Stellar Distance and Motion

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Star X has an apparent magnitude of 4.0. Star Y has an apparent magnitude of 1.0.
How much brighter is the brighter of these two stars compared to the dimmer of these two stars.
(Brightness Ratio = 2.5^Delta(m) ; Delta(m) is the difference in magnitude between the stars)
1. X is about 16 times brighter than Y
2. X is about 3 times brighter than Y
3. Y is about 16 times brighter than X
4. Y is about 3 times brighter than X
The longest living stars are those of
1. intermediate mass.
2. high mass.
3. low mass.
Where on this HR Diagram would you plot a relatively small, cool star?
1. Near the center.
2. Upper left.
3. Upper right.
4. Lower left.
5. Lower right.
A red star is _____ than a blue star.
1. brighter
2. dimmer
3. hotter
4. cooler
Where on this HR Diagram would you plot a Blue Giant star?
1. Near the center.
2. Upper left.
3. Lower left.
4. Upper right.
5. Lower right.
The distances to a star can be found by
1. Doppler shifting.
2. parallax.
3. temperatures.
4. sonar echoing techniques.
What causes the dark bands observed in a solar spectrum?
1. different chemical elements which absorb light at specific wavelengths
2. highly compressed, glowing gas
3. warmer gas in front of a source that emits a continuous spectrum
4. the emission of specific elements
Where on this HR Diagram would you plot a Red Dwarf star?
1. Near the center.
2. Upper left.
3. Upper right.
4. Lower left.
5. Lower right.
Star A has an apparent magnitude of -1.5. Star B has an apparent magnitude of +3.5.
What is the difference in magnitude between the two stars?
1. Impossible to tell
2. 4 magnitudes
3. 5 magnitudes
4. 3.5 magnitudes
Where on this HR Diagram would you plot a relatively large, hot star?
1. Upper left.
2. Lower left.
3. Near the center.
4. Lower right.
5. Upper right.
We do not see stars in the daytime because
1. skylight overwhelms starlight.
2. they simply don't exist in the daytime part of the sky.
3. of the lack of contrast with moonlight.
4. the Sun blocks their view.
Where on this HR Diagram would you plot a Red Giant star?
1. Lower left.
2. Near the center.
3. Upper left.
4. Lower right.
5. Upper right.
Star E shows a parallax angle (p) of 0.004 seconds of arc. How far away is star E from the Earth? Include units.
(Distance in parsecs = 1 / p ; Distance in light-years = 3.26 / p)
1. 4000 parsecs
2. 250 parsecs
3. 815 parsecs
4. 0.004 parsecs
Which star appears the brightest?
1. Xena
2. Ultra
3. Wabash
4. Vixon
5. Yazoo
A small-mass star will last _____ a large-mass star.
1. longer than
2. for a shorter time than
3. just as long as
Which star (or stars) would require binoculars or a telescope to see?
1. Vixon
2. Xena
3. Ultra
4. Wabash
5. Yazoo
The apparent shift in a star's position caused by the motion of the observer is called
1. luminosity.
2. apparent magnitude.
3. parallax.
4. absolute magnitude.
The brightness of a star as seen from the Earth is its
1. apparent magnitude.
2. total output.
3. absolute magnitude.
4. apparent output.
A red-shift in the spectrum of a star indicates that the star is
1. dying.
2. moving away from the Earth.
3. moving toward the Earth.
4. growing in size.
The temperature of a star is evidenced by its
1. brightness.
2. color.
3. distance.
4. rate of burning.
A man is reading a magazine one foot from a 100 watt light bulb.
How many 100 watt light bulbs would be needed to receive the same amount of light from 3 feet away?
Brightness = 1 / (Distance)^2
1. 9 bulbs
2. 3 bulbs
3. 100 bulbs
4. 1 bulb
A magnitude 11 star is _____ than a magnitude 3 star.
1. dimmer
2. cooler
3. brighter
4. hotter
The H-R Diagram, an important tool of astronomers, relates stellar temperature to stellar
1. mass.
2. brightness.
3. color.
4. distance.
Which star would appear dimmest to the unaided eye?
(Hint: on a very dark night most people can just make out a 6th magnitude star.)
1. Wabash
2. Vixon
3. Xena
4. Yazoo
5. Ultra
Where on this HR Diagram would you plot a relatively small, hot star?
1. Upper left.
2. Near the center.
3. Lower left.
4. Upper right.
5. Lower right.
Where on this HR Diagram would you plot a relatively large, cool star?
1. Lower right.
2. Upper left.
3. Upper right.
4. Near the center.
5. Lower left.
The diagrams represent the spectrums of a star and of a stationary gas here on Earth.
How is the star moving with respect to the Earth?
1. The star is moving toward the Earth.
2. The star is moving both ways.
3. The star is not moving.
4. The star is moving away from the Earth.
Where on this HR Diagram would you plot a White Dwarf star?
1. Lower left.
2. Lower right.
3. Near the center.
4. Upper left.
5. Upper right.
Where on this HR Diagram would you plot a star similar to our own sun?
1. Lower left.
2. Lower right.
3. Near the center.
4. Upper right.
5. Upper left.

Ch. 11b Stellar Distance and Motion

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