Read the assertion and reason carefully to mark the correct option ou...
The value of g at any place is given by the relation, g′ = g − ω2Recos2λ When l is angle of latitude and w is the angular velocity of earth. If earth suddenly stops rotating, then ω = 0 \ g′ = g i.e., the value of g will be the same at all places.
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Read the assertion and reason carefully to mark the correct option ou...
Assertion: If earth suddenly stops rotating about its axis, then the value of acceleration due to gravity will become the same at all the places.
Reason: The value of acceleration due to gravity is independent of rotation of earth.
The correct answer is option 'C' - If assertion is true but reason is false.
Explanation:
Acceleration due to gravity:
Acceleration due to gravity, denoted by 'g', is the acceleration experienced by an object in free fall near the surface of the Earth. It is responsible for the downward force that gives objects weight.
Effect of Earth's rotation on acceleration due to gravity:
The acceleration due to gravity varies slightly from place to place on Earth's surface due to the rotation of the Earth. This is because the Earth is not a perfect sphere and has variations in its shape and mass distribution. As a result, the gravitational force experienced by an object at different locations will be slightly different. This is known as the 'gravity anomaly'.
Effect of Earth's rotation on centrifugal force:
When the Earth rotates, a centrifugal force is generated due to the rotation. This force is directed away from the axis of rotation and is responsible for the slight bulge at the equator. The centrifugal force counteracts the force of gravity, resulting in a slightly lower effective acceleration due to gravity at the equator compared to the poles.
Assertion and Reason analysis:
If the Earth were to suddenly stop rotating about its axis, the centrifugal force would disappear, and the bulge at the equator would diminish. As a result, the distribution of mass on Earth would become more uniform, and the variations in gravitational force at different locations would decrease. Therefore, the value of acceleration due to gravity would become more or less the same at all places on the Earth's surface.
However, the reason provided for the assertion is incorrect. The value of acceleration due to gravity is not independent of the rotation of the Earth. The rotation of the Earth affects the distribution of mass and the centrifugal force, which in turn affects the value of acceleration due to gravity. Therefore, the reason is false.
Hence, the correct answer is option 'C' - If assertion is true but reason is false.
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