Question

-8 ft *4ft-4 PROBLEM 4 Determine the support reactions and the force in member CE for the truss shown in the figure below: 300 lb D 8 ft A 3 1000 lb 8 ft 8 ft

Answer 1

Solution: FBD of Frame: a 8ft 300 lb 4F+ F E Fx D 8f7 Fy A Re 53-130 B С 1ooolb Joints is poller support & F is hinge support EME=0 LE Rex 8 + 300x 12 1 000 ps S3-13 3 82 | ooo Sin S3-13 X AC =0 -EU is unknown, has to find, But AG As shown in figure, AB = BC & Bc = B GtGo but BG =GGE 4 ft :: AC- 8+8=16 ft from Re x 8 + 3600 = 17599.994 Re = 1749.999 ૨૨ 1750 lb

EF-0 Fx 1000 CUS 53:13 = 0 :. Fx -600.ool ã Gool() -ve indicates actual direction is leftward. i. Fx = Goodb (s) EFy =0 300tr louusin 53-13 + Fy=0 Fy = 500 lb (9) consider joint F sign convention compression Tension FEF F - 600 FFctfy Efx=0 -FEft 6600) = CD fef= Goo FEE = 600 lb (>) Efy=0 c09) FFctfy = FFC - Fy (fec No lb (1) 500 lb (1)

consider joint с o tan' ( 874) o=63.435 FCE aas- Rc FBc Efyzo - (-500) – Fce sino =0 Fresino =suo FE sin 63-435 SUU ! 559-017 lb :: Force in member t is 559,017 lb with 63.435 to Be Cod le. Fee has compression force.