Question map
Not attempted Correct Incorrect ★ Bookmarked
Loading…
Q58 (NDA-I/2022) Geography › World Physical Geography › Earth rotation and time Answer Verified

In a group discussion on shape and size of the Earth, three students stated the following points : 1. Student 1 : The shape of the Earth is basically an oblate spheroid. 2. Student 2 : The polar diameter of the Earth is more than the equatorial diameter. 3. Student 3 : Bulge along the equatorial region is due to revolution of the Earth. Who among the above students is /are correct?

Result
Your answer: —  Â·  Correct: A
Explanation

Student 1 is correct because the Earth's shape is an oblate spheroid, characterized by being slightly flattened at the poles and bulging at the equator [1]. Student 2 is incorrect because the equatorial diameter (approximately 12,756 km) is actually larger than the polar diameter (approximately 12,714 km) by about 42-43 km [2]. Student 3 is incorrect because the equatorial bulge is caused by the Earth's rotation, not its revolution [1]. Rotation generates centrifugal force, which is strongest at the equator, pushing mass outward and creating the bulge [2]. Revolution, the Earth's movement around the Sun, is responsible for seasonal variations rather than the planet's physical shape. Therefore, only the first statement regarding the oblate spheroid shape is accurate.

Sources

  1. [1] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 18: Latitudes and Longitudes > The Shape of The Earth and Latitudinal Heat Zones > p. 241
  2. [2] https://en.wikipedia.org/wiki/Equatorial_bulge
How others answered
Each bar shows the % of students who chose that option. Green bar = correct answer, blue outline = your choice.
Community Performance
Out of everyone who attempted this question.
50%
got it right
✓ Thank you! We'll review this.

SIMILAR QUESTIONS

NDA-II · 2015 · Q70 Relevance score: 2.14

According to the Geo-scientists, the shape of the earth is: 1. round 2. spherical 3. close to that of a sphere 4. an oblate ellipsoid Select the correct answer using the code given below:

CAPF · 2011 · Q4 Relevance score: 0.53

Statement I: The Earth is shaped more like a tangerine. Statement I : The Earth spins faster at the Poles.

CAPF · 2012 · Q53 Relevance score: -0.07

Why does the Earth assume the shape of an oblate ellipsoid?

CDS-II · 2010 · Q30 Relevance score: -0.17

The Earth is an oblate spheroid and not a perfect sphere. This is because 1. the Earth has a rotational motion and the rotational speed increases as one goes from the Poles towards the Equator. 2. the Equator experiences greater gravitational pull from the Sun. 3. the intensity of sunlight received at the Equator is greater than that at the Poles. Select the correct answer using the code given below:

NDA-II · 2009 · Q34 Relevance score: -0.34

Consider the following statements : 1. The earth’s rotation axis is not at 90° to its orbital plane, 2. The earth’s rotation axis is inclined at 23.5°. Which of the statements given above is/are correct?