What length of solid cylinder 2 cm in diameter must be taken to recast into a hollow cylinder of external diameter 20 cm, 0.25 cm thick and 15 cm long?
Mensuration
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What length of solid cylinder 2 cm in diameter must be taken to recast into a hollow cylinder of external diameter 20 cm, 0.25 cm thick and 15 cm long?

KnowledgeBoat · Accepted Answer

Given, External diameter of hollow cylinder = 20 cm So, external radius (R) = = 10 cm. Thickness = 0.25 cm Hence, the internal radius (r) = (10 - 0.25) = 9.75 cm. Length of cylinder (h) = 15 cm By formula, Given, Diameter of the solid cylinder = 2 cm so, radius (a) = = 1 cm Let h be the length of the solid cylinder, Volume = πa²h = π(1)²h = πh cm³. In order for recasting, volume of solid cylinder must be equal to volume of material of hollow cylinder . ∴ πh = 15 π x 4.9375 ⇒ h = 15 x 4.9375 ⇒ h = 74.0625 cm. Hence, the length of solid cylinder = 74.06 cm.

Mathematics

What length of solid cylinder 2 cm in diameter must be taken to recast into a hollow cylinder of external diameter 20 cm, 0.25 cm thick and 15 cm long?

Mensuration

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What length of solid cylinder 2 cm in diameter must be taken to recast into a hollow cylinder of external diameter 20 cm, 0.25 cm thick and 15 cm long?

Mensuration

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