Why do tsunamis happen?

Answer: Underwater quakes displace water

Underwater quakes displace water ✓ — Correct! Tsunamis are triggered by sudden vertical displacement of the seafloor, usually from underwater earthquakes at subduction zones. When tectonic plates suddenly shift, they push or pull huge volumes of water. This energy travels as waves at jet speed (up to 800 km/h) across the ocean! Underwater landslides and volcanic eruptions can also cause tsunamis. Wave height increases dramatically in shallow coastal waters.

Moon's gravity pulls ocean — Wrong. The moon's gravity creates tides - slow, predictable rises and falls over 6-hour periods. Tsunamis are sudden, catastrophic waves triggered by geological events like underwater earthquakes or landslides. They're completely different phenomena.

Underwater volcanoes boil water — Wrong. Underwater volcanoes don't boil water to create tsunamis. However, violent volcanic explosions can displace water suddenly, creating tsunamis. But most tsunamis come from underwater earthquakes, not volcanic activity. It's the sudden movement of Earth's crust displacing water that creates these waves.