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Question
A sinker is found to weigh 56.7 gf in water. When the sinker is tied to a cork of weight 6 gf, the combination is found to weigh 40.5 gf in water. Calculate R.D. of cork.
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Solution
Weight of sinker in water = 56.7 gf
Weight of cork = 6 gf
Wt. of sinker in water + Wt. of cork in air
= 56.7 + 6 = 62.7 gf …(1)
Wt. of cork in water + Wt. of sinker in water = 40.5 gf …(2)
Subtract eq. (1) from eq. (2)
Wt. of cork in air – Wt. of cork in water = 62.7 – 40.5 = 22.2 gf
∴ R.D. of cork =`"Weight of cork in air"/("wt. of cork in air - wt. of cork in water")`
`= 6/22.2 = 0.27`
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