Question

bending moment at a section of a beam is defined as...
o the algebraic sum of the moment of all the forces acting on one side of the section.
o the algebraic sum of all the forces acting on one side of the section.
o the algebraic sum of all the forces acting on both sides of the section.
o the algebraic sum of the moment of all the forces acting on both of the section.

Explanation:

The bending - moment at a section of a beam is defined as the algebraic sum of the moment of all the forces acting on one side of the section. This is based on the fundamental concept in structural mechanics where moments are summed to analyze the internal bending effect at a particular cross - section of a beam.

Answer:

the algebraic sum of the moment of all the forces acting on one side of the section.