A scaffold is constructed by placing two supports under a 13 ft, 9 in (a) board weighing 84 lbs. The supports are each 2 ft, 8 in (b) from their respective ends. Two painters stand on the board; one weighs 158 lbs and stands 4 ft, 11 in (c) from the left end of the board. Where must the 222 lbs painter stand so that each support carries the same weight? (express your distance in feet from the right end of the board (d).)please help!! thanks(:
Total weight = 222 + 158 + 84 = 464 lb So, each support must carry 232 lbs Working in inches: Take moment about Right hand end Board is assumed to be uniform - CG is at the center (232 x 32) + (232 x 133) = (158 x 106) + ( 84 x 82.5 ) +(222 x d)7424 + 30856 = 16748 + 6930 + 222d 222d = 14602 d = 65.77 inches Distance of 222 lb painter should be 5ft 5.77inches from Right end
