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Assume that all the mass of a galaxy is in a massive uniform density ball of...

Assume that all the mass of a galaxy is in a massive uniform density ball of stars (called bulge by astronomers), with a radius of 1 kpc. The total mass of this bulge is 3 × 1010 M⊙ The volume of a sphere with radius R is: 4/3πR3. The observed rotation curve of the galaxy is flat from 1 to 8 kpc from the center. Astronomers claim that this must be due to the presence of dark matter. How much total mass is there within 8 kpc and what fraction of that mass is in dark matter?

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Expert Solution

Here, I have used the concept of bulge and dark matter, and then using the necessary formulae regarding that, I have evaluated the answers.

genius_generous answered 1 year ago
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