[6 pts] When a body moves through a fluid or a fluid flows around a body,...

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[6 pts] When a body moves through a fluid or a fluid flows around a body, drag forces (a net force in the direction of flow) act on the body due to the pressure and shear forces on the surface of the object. Most of the information pertaining to drag on objects is a result of numerous experiments with wind tunnels, water tunnels, and other devices. Friction drag, D., which is part of the drag is primarily due to the viscosity that generates drag opposite to the motion. At high velocity, the skin friction disappears as the boundary layer becomes turbulent with a dramatic decrease in drag. The figure below shows the relationship between the skin drag 1.328 coefficient and the Re number. Empirically, it is formulated as C = where Re = and I is characteristic length in the direction of the flow. Once the friction coefficient is obtained, the friction drag can D; PUZA be calculated by; C = According to the information above, the small toy airplane that is shown in the following photo is flying at a speed of 2.5 m/s. Consider the wing as a thin, flat plate of dimension 5 cm x 30 cm and find the total drag force on the wing. Also, determine the power that must be supplied by the propeller for constant speed. 0.04 Laminar boundary 0.03 Tayer 0.02 0.01 0.00 Re Shy Stank For this calculation, assume that the friction drag. De is 50% of the total drag force. For air, use a kinematic viscosity of Vair = 15.1 10m/s and a density of pair = 1.2 kg/m. Hint: Start calculating the Re number. The power can be calculated by force X velocity. [6 pts] When a body moves through a fluid or a fluid flows around a body, drag forces (a net force in the direction of flow) act on the body due to the pressure and shear forces on the surface of the object. Most of the information pertaining to drag on objects is a result of numerous experiments with wind tunnels, water tunnels, and other devices. Friction drag, D., which is part of the drag is primarily due to the viscosity that generates drag opposite to the motion. At high velocity, the skin friction disappears as the boundary layer becomes turbulent with a dramatic decrease in drag. The figure below shows the relationship between the skin drag 1.328 coefficient and the Re number. Empirically, it is formulated as C = where Re = and I is characteristic length in the direction of the flow. Once the friction coefficient is obtained, the friction drag can D; PUZA be calculated by; C = According to the information above, the small toy airplane that is shown in the following photo is flying at a speed of 2.5 m/s. Consider the wing as a thin, flat plate of dimension 5 cm x 30 cm and find the total drag force on the wing. Also, determine the power that must be supplied by the propeller for constant speed. 0.04 Laminar boundary 0.03 Tayer 0.02 0.01 0.00 Re Shy Stank For this calculation, assume that the friction drag. De is 50% of the total drag force. For air, use a kinematic viscosity of Vair = 15.1 10m/s and a density of pair = 1.2 kg/m. Hint: Start calculating the Re number. The power can be calculated by force X velocity.