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When a star like our Sun exhausts its fuel, thermonuclear reactions in its core cease, and it collapses to become a white dwarf. Often the star will blow off its outer layers and lose some mass before it collapses. Suppose a star with the Sun’s mass and radius is rotating with period 25 days and then it collapses to a white dwarf with 60% of the Sun’s mass and a rotation period of 131 s. What’s the radius of the white dwarf? Compare your answer with the radii of Sun and Earth.
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