Question

What prevents a neutron star from collapsing and becoming a black hole?

A) Gravity in the neutron star is balanced by an outward force due to neutron degeneracy.
B) Gravity is balanced in neutron stars by the outward centrifugal force produced by their rapid rotation.
C) Gravity in the neutron star is balanced by an outward force due to gas pressure, as in the Sun.
D) Neutron stars are solid, and, like any solid sphere, they are held up by the repulsive forces between atoms in the solid matter.

Answer 1

Neutron degeneracy pressure, resulting from the Pauli exclusion principle, prevents a neutron star from collapsing into a black hole, as long as its mass is below a certain threshold.

Step-by-step explanation:

What prevents a neutron star from collapsing into a black hole is the neutron degeneracy pressure. This is a quantum mechanical force that arises because neutrons, like electrons, resist being in the same state or location due to the Pauli exclusion principle. Neutron degeneracy pressure counteracts the force of gravity attempting to compress the neutrons into an infinitely small space. However, if the mass of a neutron star exceeds a certain limit (approximately 3 solar masses), not even neutron degeneracy can prevent it from collapsing into a black hole.

The correct answer to the given question is:
A) Gravity in the neutron star is balanced by an outward force due to neutron degeneracy.