Question

The Schwarzschild radius of a black hole is the point at which the escape velocity equals that of light. Consider a sphere of mass M and radius R

(a) Using CLASSICAL physics, write down the escape velocity from the sphere’s surface. Find the value of R for which it equals the speed of light. If the mass, M, is entirely inside this radius, it is a black hole.

(b) What is this radius for a star of 10 solar masses.

(c) What is its average density inside this radius?

Answer 1