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Air at standard conditions flows along a flat plate. The undisturbed freestream speed is U0 = 20 m/s. At L = 0.4 m downstream from the leading edge of the plate, the boundary-layer thickness is δ = 2 mm. The velocity profile at this location is approximated as u/U0 = y/δ. Calculate the horizontal component of force per unit width required to hold the plate stationary.
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Fox and McDonald's Introduction to Fluid Mechanics
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