<PRE><B>Question 587317</B>
a hollow metal sphere has an internal radius of 20 cm and an external radius of 30 cm given that the density of the metal is 7.8gm/cm^3find the mass of the sphere expressing your answer in kg
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Volume of outside sphere: (4/3)pi*15^3 cu cm
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Volume of inside sphere: (4/3)pi*10^3 cu cm
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Mass = 7.8gm/cm^3[15^3-10^3] = 7.8 gm *(2375) = 17,525 gm
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Cheers,
Stan H.
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