Question

A body weighs 450 gf in air and 310 gf when completely immersed in water. Find — (i) the volume of the body, (ii) the loss in weight of the body, and (iii) the upthrust on the body. State the assumption made in part (i).

March 17, 2024

Answer

(i) Volume of the body = density of water x loss in weight

density of water = 1 g cm^-3

Given,

weight in air = 450 kgf

weight in water = 310 kgf

loss in weight = 450 – 310 = 140 gf

Substituting the values in the formula above, we get,

Volume of the body = 1 × 140 = 140 cm³

(ii) Loss in weight = 140 gf

(iii) Upthrust = loss in weight = 140 gf

The assumption in part (i) — density of water = 1.0 g cm^-3

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