The bending moment diagram of a simply supported beam carrying uniformly distributed load over the entire span is-
Parabola
A quadratic function plots as a parabola. The parabola opens downwards, indicating that the beam experiences sagging bending moment (tension at the bottom, compression at the top). Thus, the correct shape is a parabola.
Important Questions from Shear Force and Bending Moment
For a simply supported beam of length L with a triangular load that varies gradually (linearly) from zero at both ends to w per unit length at the centre, the maximum bending moment is
For simply supported beams, the bending moment at supports (or ends) is always
A cantilever of length L carries a gradually (linearly) varying load from zero at its free end to w per unit length at the fixed end. The product of deflection and flexural rigidity at the free end is
If the shear force at a section of a simply supported beam is zero, the bending moment at the section is
Shear force at any point of the beam is the algebraic sum of
