Question

40 mm 120 mm 80 mm 200 mm Problem 6 The 240 mm diameter pulley and the 200 mm lever AB are welded to axle BE which is supported by bearings C and D. If a 720 N vertical load is applied at A when the lever is horizontal, determine: a) The tension T in the cord b) The reactions at C and D. Assume that the bearing at D does not exert axial thrust and that both bearings do not resist any moment. Note: You must draw a free body diagram for the problem. Problem 6 - Solution 120 mm 720 N

Answer 1

step (1) shift the load from A to B It produce moment at A M = 720 times 200 N middot mm \r\n step(2) Also shift force T at point E It will produce a Torque moment M_T = T times 120 mm Since no other loss of moment at C/O Then M = M_T 720 times 200 = T times 120 T = 1200 N R_x rightarrow Reaction in x direction R_y rightarrow Reactioning step (3) Sigma Fy Ryc + Ryd = 720 Sigma M_d = 0 R_yc times 120 - 720 times 200 = 0 R_yc = 1200 N R_yd = 720 - 1200 = -480 M \r\n -ve shows direction of reaction opposite to assumed. Hence R_yc = 1200 N upward R_yd = 480 N Downward Now for x-axis load/Reactions R_xc + R_xd = 1200 N (1) Sigma M_c = 0 R times D times 120 = T