I came across this formula for the bending moment of a simply supported cantilever beam with a point load added in the center: M=WL/4 I am currently investigating the effect of distance between the supports in a simply supported beam on the deflection and was wondering the reason behind why the beam deflects less when the supports are brought closer. So I was studying the forces acting on the beam and wanted to understand how bending moment can suggest a reason for the problem. According to the equation, the lower the L or the distance between the supports, the lower is the bending moment. Does a lower bending moment suggest the reduced magnitude of beam defections?

  • $\begingroup$ Find out how the bending moment is related to the curvature of the beam, and how the curvature is related to the deflection. This is basic beam theory in any textbook, and on dozens of web sites. $\endgroup$ – alephzero Oct 19 at 13:23
  • $\begingroup$ @alephzero Sir, I have been trying to find this for a while now. Could you lead me to some resources, please? $\endgroup$ – Faisal Zia Oct 19 at 13:35
  • $\begingroup$ According to the relationship between bending moment and curvature, as BM decreases curvature increases. But then if the L is reduced in M=WL/4, apparently there is more deflection caused which cant be correct. $\endgroup$ – Faisal Zia Oct 19 at 15:22

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