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| The Sun |
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1. | Use the current luminosity of the Sun to estimate what it would cost to buy the power radiated by the Sun in one second as electricity at typical current billing rates for electricity. |
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2. | Use the solar constant to estimate the rate at which solar energy falls on a sunbather on a beach. You may assume the surface area of the sunbather to be about 0.5 meter squared, and neglect absorption of the radiation by the atmosphere. |
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3. | Under good seeing conditions, Earth based observations with normal telescopes are limited to an arc second or so of resolution. What is the size of a region on the Sun in kilometers that can be resolved with that resolution? |
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4. | Approximately what angular resolution is required in an Earth-based telescope to observe granulation on the surface of the Sun? |
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5. | We can measure the abundance of elements in the surface of a star like the Sun by looking at spectral intensity. It is usually assumed that the helium abundance for the Sun determined in that way holds also for the interior (outside of the core where hydrogen is being fused to helium). Do we have any checks on this rather large assumption? |
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6. | The element helium was discovered in the spectrum of the Sun. Was it found it emission or absorption? Why? |
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7. | The mass loss to the Sun from the solar wind is estimated to be about 10 million tons per year. At that rate, how long would it take the Sun to lose ten percent of its mass to the solar wind? Compare with the age of the Sun. |
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8. | If the Sun rotates once in about 25 days at the equator, what are the maximum and minimum radial velocities at the limbs? |