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Question
A piece of wax floats on brine. What fraction of its volume is immersed?
Density of wax = 0.95 g cm-3, Density of brine = 1.1 g cm-3.
Solution
Density of wax (`ρ_"w"`) = `0.95 "gcm"^-3`
Density of brine (`ρ_"B"`) = `1.1 "gcm"^-3`
Let the total volume of piece of wax be V and the volume of immersed portion be v .
According to the law of floatation ,
`"v"/"V" = ρ_"w"/ρ_"B"`
or , `"v"/"V" = 0.95/1.1 = 0.86`
or , v = 0.86 V
Thus , wax floats with 0.86th part of its volume above the surface brine .
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