Find the average density of a white dwarf star if it has a mass equal to that of the sun (2.0 × 10³⁰ kg) and a radius equal to that of the Earth (6.4 × 10⁶ m). A) 9.0 × 10⁶ kg/m³ B) 1.8 × 10⁷ kg/m³ C) 1.8 × 10⁹ kg/m³ D) 3.6 × 10¹⁰ kg/m³ E) 9.0 × 10⁷ kg/m³

Question

Quizplus · Accepted Answer

The formula for density is:

Density = mass/volume

For a white dwarf star, since it is roughly spherical in shape, the volume can be calculated using the formula for the volume of a sphere:

Volume = 4/3π(r^3)

Where r is the radius of the star.

Substituting the given values:

Volume = 4/3π(6.4 × 10^6)^3 = 1.09 × 10^20 m^3

Now, we can find the density:

Density = mass/volume

Density = (2.0 × 10^30)/(1.09 × 10^20) = 1.8 × 10^19 kg/m^3

Therefore, the closest answer choice is C, 1.8 × 10^19 kg/m^3.

Find the Average Density of a White Dwarf Star If