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Question
A solid weighs 0.08 kgf in air and 0.065 kgf in water. Find
(1) R.D. of solid
(2) Density of solid in SI system. [Density of water = 1000 kgm3]
Solution
Weight of solid in air = 0.08 kgf
Weight of solid in water = 0.065 kgf
Density of water = 1000 kgm3
(1) Relative density (RD) of solid
= Weight of solid in air
wt. of solid in air-wt. of solid in water
`= "Weight of solid in air"/("wt. of solid in air" - "wt. of solid in water")`
R.D. = `0.08/(0.08 - 0.065)`
R.D. = `0.08/0.015 = 5.3333`
(2) R.D. of solid = `"Density of solid"/"Density of water"`
`5.3333 = "Density of solid"/1000`
Density of solid = 5.3333 × 1000 = 5333.3 kgm-3
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