Air at standard conditions flows along a flat plate. The undisturbed freestream speed is \(U_{0}=20 \mathrm{~m} / \mathrm{s}\). At \(L=0.4 \mathrm{~m}\) downstream from the leading edge of the plate, the boundary-layer thickness is \(\delta=2 \mathrm{~mm}\). The velocity profile at this location is approximated as \(u / U_{0}=y / \delta\). Calculate the horizontal component of force per unit width required to hold the plate stationary.