What is the major difference between a truss and a beam?
Try it first: pick an option, then read the explanation.
Correct answer: C. A beam can't transmit load in the axial direction while a truss can
Asked in SSC JE 22/01/2018 (Morning)
Detailed Explanation
Both a beam and a truss can span a gap and carry vertical loads to the supports. The difference is how they do it.
Why “A beam can't transmit load in the axial direction while a truss can” Is Correct
A beam carries transverse load through bending moment and shear force along its length. A truss carries the same load as axial tension and compression in its triangulated members. So the distinguishing statement is (c): a beam does not transmit load axially, while a truss does.
Why the Other Options Are Wrong
- A. A beam can't transmit load in the vertical direction while a truss can: Both carry vertical loads to the supports.
- B. A truss can't transmit load in the vertical direction while a beam can: Trusses obviously carry vertical (roof, bridge) loads.
- D. A truss can't transmit load in the axial direction while a beam can: It is the reverse: trusses work axially.
Key Point
Beam: bending + shear. Truss: axial forces only.
Key Concepts for Students
- Trusses are efficient for long spans with less material.
- A deep truss behaves overall like a beam: chords take the moment, web members take the shear.
- Chord force ≈ M/h for a parallel-chord truss.
Practice more: this is question 22 in Beams and Trusses MCQs – Part 2. Try the whole set and check every answer instantly.