Different minerals are being mined from withi | vedclass

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(D) The Earth is an isolated system regarding its rotation,so its angular momentum $L = I\omega$ is conserved.When minerals are mined from deep within

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Length of day would increase

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(D) The Earth is an isolated system regarding its rotation,so its angular momentum $L = I\omega$ is conserved.When minerals are mined from deep within the Earth and used to construct multi-storeyed buildings on the surface,the mass distribution of the Earth shifts outward from the axis of rotation.This increases the moment of inertia $I$ of the Earth $(I = \sum mr^2)$.Since the angular momentum $L$ remains constant,an increase in the moment of inertia $I$ must result in a decrease in the angular velocity $\omega$ (because $L = I\omega$ implies $\omega = L/I$).Since the angular velocity $\omega$ is related to the time period $T$ by the formula $\omega = 2\pi/T$,a decrease in $\omega$ leads to an increase in the time period $T$.Therefore,the length of the day increases.

Different minerals are being mined from within the earth and multi-storeyed complexes are being constructed. Due to this activity,theoretically:

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