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The average drag coefficient for turbulent boundary layer flow past a thin plate is given by C f = 0.455/ (log 10 R el) 2.58 Where R el is the Reynolds number based on plate length. A plate 50 cm wide and 5 m long is kept parallel to the flow of water with free stream velocity 3 m/s. Calculate the drag force on both sides of the plate. For water, kinematic viscosity = 0.01 stokes

The average drag coefficient for turbulent boundary layer flow past a thin plate is given by C f = 0.455/ (log 10 R el) 2.58 Where R el is the Reynolds number based on plate length. A plate 50 cm wide and 5 m long is kept parallel to the flow of water with free stream velocity 3 m/s. Calculate the drag force on both sides of the plate. For water, kinematic viscosity = 0.01 stokes Correct Answer 63.38 N

Drag force = 2 C f (p U INFINITY/2) (l) (b) = 25.42 N per unit width.

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