Question

A body of volume 100 cm3 weighs 5 kgf in air. It is completely immersed in a liquid of density 1.8 x 103 kg m-3. Find (i) the upthrust due to liquid and (ii) the weight of the body in liquid.

March 17, 2024

Answer

Volume (V) = 100 cm² = 10^-4 m³

Weight of the body in air = 5 kgf

Density of the liquid = 1.8 × 10³ kg m^-3

Substituting the values in the formula above we get,

Upthrust = 10^-4 × 1.8 × 10³ × g = 0.18 kgf

Hence, the upthrust due to liquid = 0.18 kgf

(ii) weight of the body in liquid = weight of the body in air – upthrust

Substituting the values in the formula above, we get,

weight of the body in liquid = 5 kgf – 0.18 kgf = 4.82 kgf

Hence, weight of the body in liquid = 4.82 kgf

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