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A sheet of thickness 200 mm is rolled in a roller with roll diameter of 300 mm. If the coefficient of friction between the roll and sheet is 0.1. Find the minimum number of passes required to reduce the thickness of sheet to 180 mm?

A sheet of thickness 200 mm is rolled in a roller with roll diameter of 300 mm. If the coefficient of friction between the roll and sheet is 0.1. Find the minimum number of passes required to reduce the thickness of sheet to 180 mm? Correct Answer 7

The maximum possible reduction in a single pass will be given by: -> Δh=u2R -> Δh=(0.1)2 * 300 -> 3 mm So, in a single pass, the reduction in height is 3mm. So, after seven passes, the height will reduce to 21 mm.

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