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1 | | A star has a distance of 40 pc. What is the parallax of the star? |
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2 | | A star has a parallax of 0.2 seconds of arc. What is the distance of the star? |
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3 | | A star has a parallax of 0.11 seconds of arc. Suppose we received radio signals from creatures on a planet orbiting the star and then immediately sent a radio response to the creatures. How long would it be between the time that the creatures transmitted their signal and the time that they received our signal? |
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4 | | Suppose a star has a distance of 50 pc. What would be the parallax of the star if it were measured by creatures living on Pluto? On Mercury? |
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5 | | Star A is 4 magnitudes brighter than star B. How does the apparent brightness of star A compare with that of star B? |
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6 | | Star A is 7 magnitudes brighter than star B. How does the apparent brightness of star A compare with that of star B? |
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7 | | Star A is 16 magnitudes brighter than star B. How does the apparent brightness of star A compare with that of star B? |
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8 | | Star A has an apparent magnitude of -1. Star B has an apparent magnitude of 5. How does the apparent brightness of star A compare with that of star B? |
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9 | | Star A has an apparent brightness that is 40 times as large as that of star B. What is the difference in the magnitudes of the two stars? |
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10 | | Two stars differ by 8 in absolute magnitude. What is the ratio of their luminosities? |
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11 | | A star has an absolute magnitude of 12 and a distance of 100 pc. What is the apparent magnitude of the star? |
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12 | | At what distance does a star have an apparent magnitude that is 5 magnitudes brighter (smaller) than its absolute magnitude? |
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13 | | A star is moving away from the Earth at a speed of 200 km/s. What would be the wavelength of a spectral line that would have a wavelength of 500 nm if the star were at rest? |
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14 | | In the laboratory, the wavelength of a spectral line of an atom is 450 nm. The same line in the spectrum of a star has a wavelength of 448 nm. What is the radial velocity of the star? Is the star moving toward or away from the Earth? |
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15 | | Suppose two stars obey the mass-luminosity relationship. One star is four times as massive as the other. How do the luminosities of the two stars compare? |
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