Question

What is the term that signifies the shape of the earth?
a.Oblate Spheroid
b.Spheroid
c.Sphere
d.Geoid

Answer 1

Hint: The shape of the Earth is still a controversy. It is not round in shape, rather it is bumpy and irregular.

Complete Answer: The radius at the equator is larger than at the poles due to the long-term effects of the earth's rotation.

The shape of earth can be categorized as "Oblate spheroid" where 'Oblate' refers to a slight elliptical appearance and 'spheroid' means almost a sphere but not actually a sphere. This describes the true shape of the earth, which means flatten at the poles and bulges in the middle. Its shape is actually defined as geoid.

Moreover, the shape of the Earth is not constant.
-Sometimes this change is periodic,it influences both the ocean and the crust.
-Sometimes the change is slow as with the rise of tectonic plates .
-Sometimes the change in shape of the planet is violent during events such as earthquakes and volcanic eruptions.
-The National Geodetic Survey estimates and monitors the ever-changing planet.

Hence, the correct answer is option 'd'.The other options stand irrelevant.

Note:
-Geodesy is the science of evaluating and surveying the size and shape of the Earth, including its gravity field, and assuming the location of points on the Earth’s surface. -Earth's topographic ground is apparent with its variety of landforms and water areas. This is the difficulty for topographers, hydrographers, and geophysicists.