Page 11 - mechanics

Chapter – 2 Concurrent forces in 2D

following procedure for drawing a free body diagram:

(1) Identify the "body" you want to isolate. This body may be part of your
overall system of interest.
(2) Draw a sketch (outline shape) of the object isolated from its
surroundings, and show relevant dimensions and angles. Your drawing
should be reasonably accurate, but it can omit irrelevant details.
(3) Represent all of the external forces acting on the isolated object and
label them. Do not forget to include the weight (gravitational force) if you
are not intentionally neglecting it.
(4) Choose a coordinate system so that you can express the forces on the
isolated object in terms of components. The coordinate system should be
assigned in a way to ease solving the problem.

As examples of some free body diagrams for different cases are
shown in Figure (2.22).

TAC

A
TAB

W

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