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 th

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Q: 30 (CDS-II/2010)
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:

question_subject: 

Geography

question_exam: 

CDS-II

stats: 

0,14,34,14,15,5,14

keywords: 

{'perfect sphere': [0, 0, 2, 0], 'equator': [10, 0, 6, 7], 'oblate spheroid': [1, 0, 1, 1], 'earth': [0, 1, 1, 1], 'greater gravitational pull': [0, 0, 1, 0], 'sunlight': [0, 0, 1, 0], 'sun': [3, 0, 0, 6], 'rotational speed increases': [0, 0, 1, 0], 'rotational motion': [0, 0, 1, 0], 'poles': [5, 0, 7, 15], 'intensity': [0, 0, 0, 1]}

The correct answer is 1. The Earth is an oblate spheroid and not a perfect sphere because of its rotational motion. The Earth rotates on its axis, causing a bulging effect at the equator and flattening at the poles. This is due to the centrifugal force generated by the rotational speed of the Earth. As one goes from the poles towards the equator, the rotational speed of the Earth increases, causing a bulging effect at the equator.

Option 2 is incorrect because the equator does not experience greater gravitational pull from the Sun. The gravitational force of the Sun on the Earth is relatively constant across the entire surface.

Option 3 is incorrect because the intensity of sunlight received at the equator is not a factor that directly affects the shape of the Earth. The shape of the Earth is primarily determined by its rotation.

Therefore, only option 1 is correct in explaining why the Earth is an oblate spheroid.