Air flows at a rate of 8500 ft^3/min in a duct with square cross section (2.5-ftx2.5-ft). the duct pressure drop is 1.1 in. of water per 1000 ft of length. find the duct friction factor and the average height of surface roughness.

Asingle-geared blanking press has a stroke of 200 mm and a rated capacity of 320 kn. a cam driven ram is assumed to be capable of delivering the full press load at constant force during the last 15 percent of a constant-velocity stroke. the camshaft has an average speed of 90 rev/min and is geared to the flywheel shaft at a 6: 1 ratio. the total work done is to include an allowance of 16 percent for friction a) estimate the maximum energy fluctuation b) find the rim weight for an effective diameter of 1.2 m and a coefficient of speed fluctuation of 0.10