A cantilever AB, fixed at A and free at B, carries no transverse load (only a couple acts at the free end). The absolute value of the shear force at A is:
Try it first: pick an option, then read the explanation.
Correct answer: C. 0 kN
Asked in SSC JE 2011
Detailed Explanation
The book's figure shows a cantilever with no vertical load, so the stem is written here in words. Shear force at a section is the sum of vertical forces on one side of it.
Why “0 kN” Is Correct
With no vertical loads, vertical equilibrium gives zero vertical reaction at A, and the shear force is 0 kN at every section, including at A. A couple at the free end produces a constant bending moment but no shear.
Why the Other Options Are Wrong
- A. 1.0 kN: There is no vertical load to produce 1 kN of shear.
- B. 4.0 kN: There is no vertical load to produce 4 kN of shear.
- D. 2.0 kN: There is no vertical load to produce 2 kN of shear.
Key Point
No transverse load ⇒ zero shear force; a pure couple gives constant BM only.
Key Concepts for Students
- dM/dx = V: constant M means V = 0.
- Pure bending = constant moment, zero shear.
- The fixed end still supplies a moment reaction.
Practice more: this is question 50 in Bending and Shear Stress MCQs – Part 4. Try the whole set and check every answer instantly.