Why do tides happen twice daily?
Show answer & explanation
Answer: Moon creates two tidal bulges
Earth rotates twice per day — Wrong. Earth rotates once per day (24 hours), not twice. Two daily tides occur because the Moon creates two tidal bulges on opposite sides of Earth.
Moon creates two tidal bulges ✓ — Correct! The Moon's gravity pulls ocean water toward it (creating a bulge on the near side). On Earth's far side, inertia creates a second bulge as the Moon pulls Earth itself more than the distant water. As Earth rotates through both bulges, most coasts experience two high tides ~12.5 hours apart daily!
Ocean water sloshes back — Wrong. Water does move, but tides aren't random sloshing—they're predictable responses to the Moon's gravity creating two simultaneous bulges.
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