15.3 EQUILLIBRIUM OF FORCES AND MOMENTS

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À  p

It is often necessary to solve problems using both sums of moments and forces. Indeed, both of these sums must be equal to zero for the body to be static.

An example of a problem that has both forces and moments is given below, ([Hibbeler, 1992], prob 5-4, pg. )

[working model file]

Try the problem below,

Consider the pictures of both the hoists below, they are much like the examples that follow. The red dampers apply a force that is almost static to slow the lowering of the upper arms.

[picture]

[picture]

Lets consider another complex system to solve. In this case free body diagrams are beginning to become essential. ([Hibbeler, 1992], prob 5-44, pg. )

[working model file]

Now, lets try a problem using vectors, ([Hibbeler, 1992], prob 5-83, pg. )

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