Room temperature air flows over a horizontal smooth flat plate at a freestream speed of u = 20 m/s. the plate length is l = 1.5 m and its width is b = 0.8 m. the boundary layer is tripped at its leading edge so that it is turbulent over its entire length. using results based on the 1/7th power velocity profile, evaluate the boundary layer thickness δ at the trailing edge of the plate. calculate the wall shear stress at the trailing edge of the plate. estimate the drag (due to friction) on the portion of the plate between x = 1.0 m and the trailing edge and compare this with the drag over the first 0.5 m of the plate.

Liquid flows at steady state at a rate of 2 lb/'s through a pump, which operates to raise the elevation of the liquid 100 ft from control volume inlet to exit. the liquid specific enthalpy at the inlet is 40.09 btu/lb and at the exit is 40.94 btub. the pump requires 3 btu/s of power to operate. if kinetic energy effects are negligible and gravitational acceleration is 32.174 tt/s, the heat transfer rate associated with this steady state process is most closely 1)-2,02 btu/s from the liquid to the surroundings 2)-3.98 btu/s from the surroundings to the liquid. 3)-4.96 btu/s from the surroundings to the liquid. 4)-1.04 btu/s from the liquid to the surroundings.