Replace the force system acting on the post by a resultant force and couple mome
ID: 2176613 • Letter: R
Question
Replace the force system acting on the post by a resultant force and couple moment at point O.
The answers are Fr=416lb, Theta=35.2 degrees, and (Mr)a = 1.48 kip.ft (clockwise). This is for reference because I know what the answers should be but not how to get them. Please show all work thanks!
Replace the force system acting on the post by a resultant force and couple moment at point O. The answers are Fr=416lb, Theta=35.2 degrees, and (Mr)a = 1.48 kip.ft (clockwise). This is for reference because I know what the answers should be but not how to get them. Please show all work thanks!Explanation / Answer
tan-1(3/4) = 37 degrees
Resultant force, F = 200i + 300jsin(30) + 300icos(30) - 150icos(37) + 150jsin(37) = [200 + 259.81 - 119.8]i + [150 + 90.27]j = 340i + 240.27j = [3402 + 240.272] = 416.33lb
= tan-1(240.27/340) = 35.24
Mo = [2jX200i] + [6jX{300jsin(30) + 300icos(30)}] + [4jX{ -150icos(37) + 150jsin(37)}] = -400k - 1558.86k + 479.24k = -1479.62k[anti-clockwise] = 1479.2 clockwise = 1.48kip.ft