Which scientist, in considering his attraction theory, postulated that the rotating Earth should be flattened at the poles?

• A. Copernicus
• B. Kepler
• C. Galileo
• D. Newton

Answer: (D)

Rotation creates a centrifugal effect that weakens gravity at the equator. In Newton’s gravity framework, a rotating Earth behaves like a self-gravitating fluid: gravity pulls everything toward the center, while the outward tendency from rotation makes the equator bulge. The surface settles where these forces balance, producing an oblate spheroid—flattened at the poles and wider at the equator. This is why the Earth isn’t a perfect sphere but is slightly squashed at the poles. Copernicus, Kepler, and Galileo made crucial astronomical contributions, but Newton specifically linked rotation to the Earth’s flattened shape through his attraction theory.