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प्रश्न
When does an object float or sink when placed on the surface of a liquid ?
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उत्तर
When an object is placed on the surface of water, two forces act on the object:
(i) The gravitational force that act in the downward direction.
(ii) The upthrust or the buoyant force that act in the upward direction.
An object floats on the surface of water if the upthrust of water on the object is greater than the weight of the object. An object sinks if the weight of the object is greater than the upthrust of water on the object.
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संबंधित प्रश्न
What is meant by the term ‘buoyancy’ ?
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- Name the parts labelled by the letters X and Y.
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- Give reasons for what happens to valves A and B in part (ii).
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- Give a reason for your answer in part (v).
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