posted by bob on .
After the Sun exhausts its nuclear fuel, its ultimate fate may be to collapse into a white dwarf state. In this state, it would have approximately the same mass as it has now, but its radius would be equal to the radius of earth.
(a) Calculate the average density of the white dwarf.
(b) Calculate the acceleration of a mass in free fall near the surface of this white dwarf.
(c) Compare density of the white dwarf to the density of anything else you may be familiar with.
You need to do some looking up of numbers. Chief among them are:
Earth radius Re = ___
Solar mass M = ___
Universal gravity constant = G
= 6.67*10^-11 N*m/kg^2
(a) avg. density = M/[(4/3)*pi*Re^3)
(b) g = G M/Re^2
(c) For water, the density is
(rho)w = 1000 kg/m^3
Compare to that.