Everything Science Grade 11

12.2 CHAPTER 12. FORCE,MOMENTUM AND IMPULSE

Free Body Diagrams ESBEU

In a free-body diagram,the object of interest is drawn as a dot and all theforces acting on it are drawn
as arrows pointing awayfrom the dot. A free body diagram for the two-trailer-system will therefore
look like this:

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F 1 : Force of car on trailers (to the right)

Ff: Frictional force on trailers (to the left)

Fg: Downward force of Earth on trailers

FN: Upward force of road ontrailers

F 1

Fg

FN

Ff

Example 2: Free body diagram

QUESTION

Draw a free body diagram of all the forces acting on trailer A in the example above.

SOLUTION

Step 1 : Draw a dot to indicatethe object

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Step 2 : Draw arrows to indicate all the forces acting on the object