ENB205 Lecture Notes - Lecture 5: Free Body Diagram
Document Summary
Individual objects or members are isolated from their environment or system, illustrating all external forces acting upon them. A straight line push or pull acting upon an object, vector quantity has direction and magnitude. The twisting effort about a point or axis when a force is applied at a distance. Arc with an arrowhead acting about a point, indicating direction of cw or ccw. Magnitude is illustrated by length of line segment and is the amount of push or pull. Moment (m) = force (f) * distance (d) Distance (d) is called the moment arm; it must be measured perpendicular to the line of action of the force. Free body diagram procedure: sketch the isolated object, sketch the applied and normal forces, label objects and forces, label dimensions. Replaced with two reaction forces one vertical (y) and one horizontal (x) Replaced with one reaction force, perpendicular to surface. Replaced with two forces: one horizontal and one vertical, and one moment.
