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Relativity FAQ

A black hole's event horizon is the boundary where:

Nothing, not even light, can escape from inside. Inside the event horizon all future-directed paths lead inward, so escape is impossible.

Short Answer

Nothing, not even light, can escape from inside is the best answer.

Relativity questions test whether space, time, energy, and simultaneity are being treated classically when they should not be. Start by deciding whether the question is special relativity, general relativity, or an observational consequence such as GPS timing.

Inside the event horizon all future-directed paths lead inward, so escape is impossible.

Why This Answer Is Correct

This is a Easy-level question in Relativity. The prompt is really testing whether you can connect the concept to its defining physical relationship instead of picking a nearby-but-wrong term.

Most relativity mistakes come from mixing Newtonian intuition with relativistic invariants such as spacetime interval, proper time, or rest energy.

Choices At A Glance

  • A. Matter becomes massless
  • B. Nothing, not even light, can escape from inside
  • C. Gravity becomes zero
  • D. Time stops everywhere in the universe

When similar options appear on an exam, eliminate the ones that break the core law, use the wrong units, or confuse a definition with a consequence.

Topic Snapshot

Topic: Relativity

Difficulty: Easy

Best next move: Re-state the governing law in your own words, then solve one more example from the same topic before moving on.