Meriam, Kraige & Bolton — Statics of Particles: Problem 2_17

⚡ Mecademy AIENG정역학 · ch2  Problem Statement 2/17 The ratio of the lift force to the drag force for the simple airfoil is . If the lift force on a short section of the airfoil is 50 lb, compute the magnitude of the resultant force and the angle which it makes with the horizontal. Problem 2/17 (a) Magnitude of the Resultant Force ● Calculation Process 1. Present Final Formula: The resultant force is the vector sum of the lift force and the drag force . Since these forces are perpendicular (lift is vertical and drag is horizontal), the magnitude is given by the Pythagorean theorem: 2. Determine the Drag Force : Given the ratio and the lift force : 3. Substitute Values: Substitute and into the resultant formula: 4. Final Calculation: ● Final Conclusion: The magnitude of the resultant force is (to three significant figures). (b) Angle with the Horizontal LDL/D=10 Rθ R RL D R= L+D 22 D = D L 10L=50 lb D= = 10 L = 10 50 5 lb L=50 lbD=5 lb R= 50+5 22 R= = 2500+25 2525 R≈50.25 lb R=50.2 lb θ ● Calculation Process 1. Present Final Formula: The angle that the resultant force makes with the horizontal (the direction of the drag force ) is found using the tangent function: 2. Substitute Values: Since the ratio is given as 10: 3. Final Calculation: Using a calculator for the inverse tangent of 10: ● Final Conclusion: The angle that the resultant force makes with the horizontal is . ✨ Final Answer Summary (a) Magnitude of resultant force: (b) Angle with the horizontal: Mecademy AI Solutio