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EXERCISE 7

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EXERCISE 7


The Sun has a mass of 2.0 * 10^30 kg and a radius of 7.0 * 10^5 km.  

(a) What is the average density of the
Sun compared to the density of air (1 kg/m^3), water (1000 kg/m^3), 
rock (2800 kg/m^3), and iron (7900 kg/m^3)?  Using only the density
information, with no knowledge of the Sun's internal structure, would 
you most likely conclude that the Sun is primarily solid, liquid, or gas?

(b) It turns out that the density within a few thousand km of the 
center of the Sun is about 110 times that of water.  Using this
information, and the average density calculated in Part (a) above,
would you most likely conclude that the Sun is primarily solid, liquid,
or gas?  Explain your reasoning.  You may
wish, for example, to compare the Sun's density distribution to that of
a mostly solid object (e.g. Earth) or mostly gaseous object (e.g. Jupiter).
You don't have to, however, to get a well-reasoned answer.