Meriam, Kraige & Bolton — Statics of Particles: Problem 2_52

⚡ Mecademy AIENG정역학 · ch2  Problem Statement 2/52 The caster unit is subjected to the pair of 80-lb forces shown. Determine the moment associated with these forces. Problem 2/52 ● Calculation Process 1. Identify the Force System: The problem describes a pair of equal and opposite forces ( ) that are parallel but not collinear. Such a system constitutes a couple. The moment of a couple is independent of the reference point and is equal to the product of the magnitude of one of the forces and the perpendicular distance between their lines of action. 2. Present Final Formula: The magnitude of the moment of a couple is given by: where: is the magnitude of the force. is the perpendicular distance (moment arm) between the forces. 3. Substitute Values: From the provided diagram: Substituting these into the formula: 4. Final Calculation: 5. Determine the Direction: By observing the diagram, the 80-lb force on the left acts upward, while the 80-lb force on the right acts downward. This configuration tends to rotate the caster unit in a counter-clockwise (CCW) direction. In standard 2D statics convention, a counter-clockwise moment is considered positive. F=80 lb M M=F⋅d F d F=80 lb d=1.4 in. M=80 lb×1.4 in. M=112 lb⋅in. ● Final Conclusion: The moment associated with the pair of forces is in the counter- clockwise direction. ✨ Final Answer Summary Moment of the couple: Mecademy AI Solution · ENGProblem 2/52 M=112 lb⋅in. 112 lb⋅in. (Counter-clockwise)