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GATE 2020 CE (CE1) – Question 15

Structural Analysis · Deflections of determinate beams, frames and trusses · 1 mark · Multiple choice

The planar truss is shown, not to scale. Neglecting member self-weight, find the number of zero-force members under load P.

Diagram for GATE 2020 CE (CE1) question 15
  1. 6
  2. 7
  3. 8
  4. 9

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Show answer and explanation

Correct answer: (C) 8

Explanation

Start at the unloaded free right end:both incident members vanish. Apply the unloaded-joint rules backward through the right bay to obtain six zero members there. At the loaded lower joint,the vertical member balancesP,so the inclined lower-left member is zero. The vertical member joining the two fixed support nodes has no axial deformation and hence no force. Total **8,C**. The remaining three members carry the load to the supports.