Question

3. Find a reaction forces at A and B using the free-body diagram of the entire truss (10p). b. determine the force in members BC, BE and EF of the truss. Indicate whether the members are in tension or compression (10p). Take =Last number of your ID b = Second number of your ID (m) P = Eighth number of your ID a (kN) If any term (a, b or P) is zero, take 1. 1 D р a P E a --b-
   a=6 b=6 c=2

Answer 1

Page 1 KN I kn a ; b=6 m ک) E ) P F a G 6100 > Fx = 0 RAH - 2+2+2 Free body diagram १ - 6 * G TRAH {fyzo RA+RGv= 2 2 ZM = 0; 6 Rar* b = 2*6+2*12+2*18 +2*6 RGV*6 = 84 * 1 Ray 14 KN RAH 6 = Rov Ra4=6 A KN -12 * Rara R = 12 Ray-14 AV Reaction forces. csscanned with CamScanner

Page 2 By the method of section 2 6 ... 2 Section X- Passes x-x passes through di E 6 X. BC_BE EF. 6 x IA F 2 6 6.50 Taking any side of section upper section 6 . 2 6 G 14 E 12 2 ploc G F + BC FEF Moment about B FBE b Bet ? must be considered sember's forces In the method of section forces must be Ceither) any sides (ony appeared external forces and one side) cut = 0 B 2*12 +246 +2*6 + Fer*6 so EF 48 *6 = FEF -8 KN M E=0 FFEF= moment about E':- 2*6 - F&c*6 =o FB C *6 =2*6 -2 KN EBE CS$canned with CamScanner

Page-3 Moment about F =0 Fec* 6 + FREY xx 2x12 +2+6 E half of hypoteringen 2852 of square ÇE 2= BE EBE B 6 8.485 = 4.24264 2 4.242664 2*12 + 2x62x6 FBE* FB C = 2 24 FBE 4.242664 KN FBE 5-6568 Force in members in Tension BC 2 KN in Tension BE = 5.656 KN in compoussion EF = 8KN CSScanned with CamScanner