Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

a utility pole is loaded with three forces as shown. Using the tip to tail metho

ID: 2271553 • Letter: A

Question

a utility pole is loaded with three forces as shown. Using the tip to tail method, determine the force F3 (horizontal) such that the resultant of all the three forces is vertical. Also, what is the magnitude of the resultant? suggested sequence: F1 to F2 to F3: Scale: 1/4 inch = 10 lb.

a utility pole is loaded with three forces as shown. Using the tip to tail method, determine the force F3 (horizontal) such that the resultant of all the three forces is vertical. Also, what is the magnitude of the resultant? suggested sequence: F1 to F2 to F3: Scale: 1/4 inch = 10 lb.

Explanation / Answer

Angle of F2 from vertical = atan(3/4) = 36.87 deg

Resolving F1 and F2 in x and y directions:


F1x = -180*sin30 = -90 lb

F1y = -180*cos30 = -155.88 lb


F2x = 90*sin36.87 = 54 lb

F2y = -90*cos36.87 = -72 lb


Net x-direction force = 0.

So, 0 = -90 + 54 + F3


or F3 = 36 lb


Net y-direction force = -155.88 - 72 = -227.88 lb

Magnitude of resultant = 227.88 lb