Question

Polar diameter of the earth is shorter than equatorial diameter by about
A 43km
B 82km
C 56km
D 101km

Answer 1

Hint: 1)The difference between the polar diameter of the earth and the equatorial diameter is less than 50 km.
2)The centrifugal force causes an increase in the diameter of the equator.

Complete answer:
An equatorial bulge is a contrast between the central and polar breadths of a planet, because of the centrifugal power applied by the revolution about the body's axis. A rotating body will in general shape be an oblate spheroid as opposed to a circle.
Earth is more extensive in the center and complements at the posts than an ideal circle. The equatorial width of Earth is around 7926 miles or 12,756 km while the polar measurement is 7900 miles or 12,714 km. The central periphery is roughly 24,900 miles (40,075 km). The difference between the two is 43 km.
The most remarkable special cases are the Mariana Trench – the deepest spot on Earth, at 10,911 m (35,797 ft.) underneath ocean level – and Mt. Everest, which is 8,848 meters (29,029 ft.) above ocean level. In any case, these two land highlights speak to a minor variety when contrasted with Earth's general shape – 0.17% and 0.14% separately.
Hence, the correct answer is option (A)

Note: Due to the inconsistency between Earth's polar and equatorial measurements, cosmologists and researchers regularly utilize midpoints. This is what is known as its "mean radius", which for Earth's situation is the amount of its polar and central measurements, which is then separated fifty-fifty. From this, we get a mean distance across of 12,742 km (7917.5 mi).
The distinction in Earth's width has regularly been significant with regards to arranging space dispatches, the circles of satellites, and while circumnavigating the globe.