Second moment of area for triangle trough x-axis = (ah3)/36

The second moment of area, also known as the moment of inertia, is a measure of an object's resistance to bending or deformation when subjected to a force. It quantifies how the object's mass is distributed around its axis. It is often used in engineering and physics to analyze the strength and stiffness of structural components.

The relation between bending moment and the second moment of area of the cross-section and the stress at a distance y from the neutral axis is

stress=bending moment * y / moment of inertia of the beam cross-section

A moment in time would normally be longer than a second, therefor a second would be faster.

Structural steel members are the I-beams which consist second moments of area (moment of inertia of plane area), it allow them to be very stiff in respect to their cross-sectional area.