An Introduction to Modern Astrophysics · Problem 24.34
The Early Universe — Carroll & Ostlie
Physics — Astrophysics · roche-limit-black-hole
Problem
Using Newtonian gravity, estimate the Roche limit of a supermassive black hole of mass 3.7×106 M⊙ (assume that a 1 M⊙ main-sequence star is tidally disrupted). How does your answer compare with the black hole's Schwarzschild radius? Hint: Begin with Eq. (19.4), substituting the appropriate average densities and radii.