A hollow spherical shell is made of a metal with a density of 6 grams per cubic centimeter. If the inner and outer radii of the shell are 8 centimeters and 9 centimeters, respectively, find the weight of the shell in kilograms.
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Correct answer: D
Explanation
Density = 6 g/cm³
Inner radius = 8 cm
Outer radius = 9 cm
Volume (Shell) = (4/3)π(R³ − r³)
Volume = (4/3)π(9³ − 8³)
= (4/3)π(729 − 512)
= (4/3)π(217)
Weight = Density × Volume
Weight = 6 × (4/3)π × 217 = 1736π g
= 1736 × 22/7 = 5456 g = 5.456 kg