Stars with masses greater than or equal to how many solar masses will collapse into a black hole?

• A. 5
• B. 8
• C. 10
• D. 20

Answer: (C)

When massive stars die, their fate is decided by how much mass their core has left after burning fuel. If the core is heavy enough that neutron degeneracy pressure can’t support it, gravity dominates and the core collapses into a black hole. In many introductory treatments, stars born with initial masses around ten solar masses or more end their lives with cores that are heavy enough to form black holes, so they collapse directly or after a supernova. Lighter stars typically leave neutron stars or white dwarfs instead. The ten-solar-mass threshold is a convenient, approximate dividing line used in basic astronomy to separate outcomes: above it, black holes are the likely result; below it, neutron stars (or white dwarfs) are more common. Real outcomes can vary with details like mass loss and composition, but this is the standard teaching point.