4-82. Express the moment of the couple acting on the pipe assembly in Cartesian vector form. What is the magnitude of the couple moment? n di M 20 lb 3 ft В 1 ft 1.5 ft 20 lb 2 ft 1 ft 28-Ado19 Prob. 4-82

*4–8. Determine the moment of each of the three forces about point B. Fj = 250 N 30 F2 = 300 N 60 -2 m- -3 m- 4 4'm В 3 F3= 500 N

4-27. Replace the three forces acting on the plate 1 wrench. Specify the magnitude of the force and co moment for the wrench and the point P(y, z) where its of action intersects the plate. Z x A FA = {-80k}lb 12 ft. Z B Prob. 4-27 FB=(-60j] lb 12 ft C Fc-40i) lb

4-57. Determine the moment of this force F about an axis extending between A and C. Express the result as a Cartesian vector. X 4 ft 3 ft A Z 2 ft C B in Ch y F = {4i + 12j3k} lb