Why do some stars end up as black holes but others dont?
The answer given by the Department of Physics Virginia Tech; The answer involves the gravity and the internal pressure within the star. These two things oppose each otherthe gravitational force of the star acting on a chunk of matter at the stars surface will want to cause that matter to fall inward, but the internal pressure of the star, acting outward at the surface, will want to cause the matter to fly outward. When these two are balanced (i.e. equal in strength) the star will maintain its size: neither collapse not expand. Such is the case for the Sun at the moment, and even, for that matter, for the Earth. However, when a star runs out of nuclear fuel, and therefore continues to lose energy from the surface (it is emitting light energy), while not replacing the lost energy through nuclear fusion (no more nuclear fuel), gravity will win out over the internal pressure and the star will contract slowly or collapse quickly depending upon the details of the internal structure and compo
