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Question
A solid of density 5000 kg m-3 weighs 0.5 kgf in air. It is completely immersed in water of density 1000 kg m-3. Calculate the apparent weight of the solid in water.
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Solution
Density of solid = 5000 kg m-3
Weight of solid = 0.5 kgf
Density of water = 1000 kg m-3
Here , Upthrust = Volume of the solid × density of water × g
= `(0.5/"g")/5000 xx 1000 xx "g"`
= `0.5/(5000 xx "g") xx 1000 xx "g" = 0.1` kgf
Apparent weight = True weight - Upthrsut
= 0.5 - 0.1 = 0.4 kgf
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