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Two statements are given, Assertion A and Reason R. Assertion A: As one moves from the poles to the equator, the acceleration due to gravity always points toward the Earth's centre and its magnitude stays the same. Reason R: At the equator the acceleration due to gravity is directed toward the centre of the Earth. Choose the correct option.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is NOT the correct explanation of A.
3. A is true but R is false
4. A is false but R is true

Correct answer: A is false but R is true

Solution

Because of the centrifugal effect of rotation, effective g is largest at the poles and smallest at the equator, and it is exactly radial only at the poles and equator. So A (constant magnitude, always radial) is false. At the equator the centrifugal term is anti-parallel to gravity, so effective g is still radial; R is true.

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