Question

What is the event horizon of a black hole?

A) "surface" at which any object passing through it will leave with greater energy than it entered
B) "surface" at which all events happen
C) infinitesimally small volume at the center of the black hole that contains all of the black hole's mass
D) "surface" from inside of which nothing can escape

Answer 1

The event horizon of a black hole is the boundary of the black hole where the escape velocity equals the speed of light. Inside the event horizon, nothing can escape, not even light. The size of the event horizon depends on the mass of the black hole.

Step-by-step explanation:

The event horizon is the boundary of a black hole. It is the region where the escape velocity equals the speed of light, meaning that nothing, not even light, can escape from inside the event horizon. The size of the event horizon depends on the mass of the black hole, with more massive black holes having larger event horizons. The event horizon is the point at which all events happen within the black hole and separates the trapped objects inside from the rest of the universe.