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प्रश्न
When tall building are constructed on earth, the duration of day-night slightly increases. Is it true?
उत्तर
Yes, because tall buildings have their CM much above the ground. It increases moment of inertia of the Earth. As the Earth’s rotation does not involve torque, its angular momentum is constant. Thus, an increase in MI leads to lower angular velocity of the Earth about its axis of rotation. This means length of night and day will increase. However, the increase is very small.
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संबंधित प्रश्न
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[Hint : The force acts along the normal to the sphere
through the contact. Treat the collision as onedimensional
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