# Determine the density of the white dwarf Sirius B if it is known that its radius is 3 times the radius of the Earth

September 16, 2020 | Education

| **Determine the density of the white dwarf Sirius B if it is known that its radius is 3 times the radius of the Earth, and its mass is almost equal to the mass of the Sun.**

Radius R = (6.37 * 10 ^ 6 m) * 3 = 1.911 * 10 ^ 7 m

Mass M = 2 * 10 ^ 30

Density = M / (4/3 * pi * R ^ 3) = 2 * 10 ^ 30 / (4/3 * pi * (1.911 * 10 ^ 7) ^ 3) = 68.4 million kg / m3

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