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प्रश्न
Why does a ship make of iron not sink in water, while an iron nail sinks in it?
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उत्तर
Density of iron is more than density of water, therefore weight of iron nail is more than wt. of water displaced by it and nail sinks. While shape of iron ship is made in such a way that it displaces more weight of water than its own weight. Secondly, the ship is hollow and the empty space contains air which makes the average density of ship less than that of water and hence ship floats on water.
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