N annealed copper strip 9 inches wide and 2.2 inches thick, is rolled to its maximum possible draft in one pass. The following properties of annealed copper are given: strength coefficient is 90,000 psi; true strain at the onset of non-uniform deformation is 0.45; and, engineering strain at yield is 0.11. The coefficient of friction between strip and roll is 0.2. The roll radius is 14 inches and the rolls rotate at 150 rpm. Calculate the roll-strip contact length. Calculate the absolute value of the true strain that the strip undergoes in this operation. Determine the average true stress of the strip in the roll gap. Calculate the roll force. Calculate the horsepower required.