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A cylindrical jar of radius 6 cm contains oil. Iron spheres each of radius 1.5 cm are immersed in the oil. How many spheres are necessary to raise the level of the oil by two centimeters? |
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Answer» Given that, radius of cylindrical jar, r = 6 cm Depth/height of the jar, h = 2 cm Volume of the jar, V’ = πr2 h ⇒ V’ = π (6)2 (2) cm3 Radius of the sphere = 1.5 cm So, volume of the sphere = \(\frac{4}{3}πr^3\) = \(\frac{4}{3}π(1.5)^3\) Volume of oil in cylindrical jar = volume of n spheres needed to raise the level by 2 cm ∴ π (6)2 (2) = \(n\times\frac{4}{3}π(1.5)^3\) ⇒ n = 16 ∴ number of iron sphere needed = 16 |
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