(a) What is the shape of the earth? (b) With the aid of appropriate diagrams, give four proofs to support your answer in (a) above

Answer Details

 (a)

The Earth is an oblate spheroid. This means it is mostly spherical but slightly flattened at the poles and slightly bulging at the equator due to its rotation.

(b)

(i) sunrise and sunset: The earth rotates from west to east which means t places in the east see the sun before places in the west. If the earth was that flat, all places would see the sun the same time. 

(ii) A Ship's Visibility: The diagram below illustrates how an observer can see only one of the two ships. This observation supports the Earth's curvature: as a ship sails away from shore, it gradually disappears from view starting from the bottom up. If the Earth were flat, the entire ship would vanish simultaneously.

(iii) Eclipse of the Moon: During a lunar eclipse, the Earth casts a shadow on the Moon that is always round, a phenomenon that is consistent with a spherical shape, as only a sphere can cast a circular shadow regardless of its orientation relative to the light source. If the Earth were flat, the shadow would have a different shape depending on the angle of the light.

(iv) Circumnavigation of Earth; The Earth has been circumnavigated several times by land, sea, and air, a feat that supports the concept of a spherical shape, as it involves traveling all the way around the Earth and returning to the starting point, a journey completed by numerous explorers and modern aircraft.