Moment of a beam refers to the ability of a beam to resist bending and is defined as its section modulus multiplied by stress. This can be further explained as follows:

Definition of moment of a beam:

• The moment of a beam refers to the bending moment that is produced when a load is applied to it.

• It is the ability of a beam to resist bending and is calculated by multiplying the section modulus of the beam by the stress it is subjected to.

• The section modulus of a beam is a property that describes its resistance to bending.

Explanation of the equation:

• The equation for the moment of a beam is given by M = σZ, where M is the bending moment, σ is the stress, and Z is the section modulus.

• The section modulus is a property of the beam that relates the moment of inertia to the distance from the neutral axis.

• The moment of inertia is a measure of the beam's resistance to bending and is proportional to the square of the depth of the beam.

• The coefficient of elasticity is a property of the material that the beam is made of and relates the stress to the strain.

• Therefore, the moment of a beam is a function of its geometry, the material it is made of, and the load it is subjected to.

Conclusion:

• In summary, the moment of a beam is defined as its section modulus multiplied by stress.

• The section modulus is a property of the beam that relates the moment of inertia to the distance from the neutral axis.

• The moment of inertia is a measure of the beam's resistance to bending and is proportional to the square of the depth of the beam.

• The coefficient of elasticity is a property of the material that the beam is made of and relates the stress to the strain.

• Therefore, by understanding these properties and their relationships, we can calculate the moment of a beam and determine its ability to resist bending.

Moment is equal to bending stress and section modulus M=fz
where z is section modulus is equal to I/y