A piece of copper having an internal cavity weights 264 g in air and 221 g in water. The density of copper is 8.8 gm–3. What is the volume of the cavity?


Correct option is

13 cm3


Apparent loss of mass of copper = 264 – 221 = 43 g. This is the mass of water displaced by copper piece when it is immersed in water. Volume of copper piece with cavity = 43 cm3. Volume of copper only is .

Therefore, the volume of the cavity = 43 – 30 = 13 cm3.




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