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Fluid Mechanics — JEE physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 ScienceJEE physicsFluid Mechanics1 Mark
Question
Assertion : To float, a body must displace liquid whose weight is greater than the actual weight of the body.
Reason : The body will experiences no net downward force, in the case of floating.
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Answer

(c) Net force $=$ actual weight - upthrust force$=$ Actual weight - Weight of liquid displaced.The body will rise above the surface of liquid to such an extent that the weight of the liquid displaced by the immersed part of the body (i.e. upward thrust) becomes equal to the weight of the body. Thus the body will float when upward thrust is more than its actual weight. In this special case the density of solid body is less than the density of liquid.

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