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Find the coefficient of friction of the roll having diameter 100 mm and the maximum possible reduction is 1 mm?

Find the coefficient of friction of the roll having diameter 100 mm and the maximum possible reduction is 1 mm? Correct Answer 0.1

The maximum possible reduction in a single pass is equal to: -> Δh=u2 R; where u is coefficient of friction, and R is roll diameter. -> 1=u2 100 -> u = √1/100 =0.1 -> coefficient of friction is equal to 0.1.

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