Estimate the drag of a thin square plate (3 m by 4 m) when it is towed through water (10°C). Assume a towing speed of about 5 m/s. Use Table 11.1 in §11.3. 

In Table 11.1

a. The plate is oriented for minimum drag.

b. The plate is oriented for maximum drag.

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TABLE 11.1 Approximate Cp Values for Various Bodies Type of Body Length Ratio Co Re Rectangular plate Vb = 1 >10 >10 1.18 Ub = 5 1.20 Ub = 10 >10 >10 >10 1.30 Ub = 20 1.50 Ub = 00 1.98 Circular cylinder with axis parallel to flow Ud = 0 (disk) Ud = 0.5 >10 >10 >10 1.17 - O)) 1.15 Ud = 1 0.90 Ud = 2 >10 >10 >10 0.85 Ud = 4 0.87 Ud = 8 0.99 Square rod >10 2.00 Square rod 1.50 >10 60 Triangular cylinder >10 1.39 - Semicircular shell >10 1.20 - Semicircular shell >104 2.30 - Hemispherical >10 0.39 Hemispherical shell >10 1.40 Cube - >10 1.10 Cube >10 0.81 - Cone-60 vertex >10 0.49 Parachute 3 X 10" 1.20 8 8 8