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2.4: Concurrent Forces

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    50575

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    A set of point forces is considered concurrent if all the lines of action of those forces all come together at a single point.

    A traffic light held in midair by two cables, with the two tension forces and the gravitational force on the light drawn in as vectors.
    Figure \(\PageIndex{1}\): Because the lines of action for the gravitational force and the two tension forces line up at a single point, these forces are considered concurrent.
    A two-legged table with the contact force on each leg and the gravitational force on the table's center of mass drawn in as vectors.
    Figure \(\PageIndex{2}\): Because the lines of action of the gravitational force and the two normal forces do not intersect at a single point, these forces are not considered concurrent. Adapted from Public Domain image by Seahen.

    Because the forces all act through a single point, there are no moments about this point. Because no moments exist, we can treat this body as a particle. In fact, because real particles only exist in theory, most particle analysis is actually applied to extended bodies with concurrent forces acting on them.

    Video lecture covering this section, delivered by Dr. Jacob Moore. YouTube source: https://youtu.be/puLnyApKfuc.

    This page titled 2.4: Concurrent Forces is shared under a CC BY-SA 4.0 license and was authored, remixed, and/or curated by Jacob Moore & Contributors (Mechanics Map) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.