What is the Coriolis effect?

• A. It describes gravity pulling objects toward the Earth's center.
• B. It is caused by the Earth's rotation causing moving objects to curve, veering right in the Northern Hemisphere and left in the Southern.
• C. It measures humidity changes.
• D. It explains why tides occur.

Answer: (B)

The Coriolis effect is the apparent deflection of moving objects caused by observing motion from a rotating frame of reference. As the Earth turns, different latitudes move at different speeds, so a path that would be straight in an inertial sense appears curved when viewed from the surface. This makes moving objects veer to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. This deflection helps explain large-scale wind patterns and storm rotations, not gravity, humidity changes, or tides.