Which statement about the Coriolis Force is correct?

• A. It is caused by Earth's rotation and deflects air to the right in the Northern Hemisphere.
• B. It is caused by differences in air density and has no relation to latitude.
• C. It acts to accelerate wind toward low pressure directly.
• D. It is strongest at the equator and zero at the poles.

Answer: (A)

The Coriolis effect comes from Earth's rotation and causes moving air to be deflected sideways rather than moving straight toward its original path. In the Northern Hemisphere this deflection is to the right of the motion. That is why the statement describing the Coriolis force as being caused by Earth's rotation and deflecting air to the right in the Northern Hemisphere is correct. This effect does not originate from changes in air density; density differences drive buoyancy and pressure-related flows, but the Coriolis force itself is tied to rotation and latitude. It also does not accelerate wind directly toward low pressure—the pressure gradient force does that, while the Coriolis force redirects the wind's path at right angles to that acceleration. Additionally, the Coriolis effect is zero at the equator and increases with latitude, becoming strongest near the poles, so the idea that it is strongest at the equator is incorrect.