GATE 2022 CE (CE1) – Question 50
The plane truss shown in the figure is subjected to an external force P. It is given that P = 70 kN, a = 2 m, and b = 3 m. The magnitude (absolute value) of force (in kN) in member EF is _______. (round off to the nearest integer)
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Correct answer: 35
Explanation
At joint I, the two members are non-collinear and there is no external load, so GI and IJ are zero-force members. Joint H similarly makes GH zero.
The global vertical reaction at J is $70(4/8)=35$ kN by moments about A. At J the diagonal GJ has a 3:2 vertical-to-horizontal ratio, so its horizontal component is $35(2/3)$. Joint F balances that diagonal’s vertical component with EF. Therefore **|EF|=35 kN**.