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Question
A jeweller claims that he makes ornaments of pure gold that has a relative density of 19.3. He sells a bangle weighing 25.25 gf to a person. The clever customer weighs the bangle when immersed in water and finds that it weighs 23.075 gf in water. With the help of suitable calculations, find out whether the ornament is made of pure gold or not.
[Hint : calculate R.D. of material of bangle which comes out to be 11.6].
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Solution
R.D. of pure gold = 19.3
Weight of bangle in air, W1 = 25.25 gf
Weight of bangle when completely immersed in water W2 = 23.075 gf
R.D. of bangle = `W_1/(W_1 - W_2) xx "R.D. of water"`
R.D. of bangle = `25.25/(25.25 - 23.075) xx 1`
R.D. of bangle = 11.6
The bangle is not made of pure gold as its density is not 19.3.
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