5. MOMENTS

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À  p

a force is an important type of mechanical effect, but it doesn't explain bending. For this we use moments.

The classic example is the see-saw,

Consider the case of a vise. The bottom member must resist the moment caused when the jaws are tightened.

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If we look at a normal step ladder we can see that both halves can be analysed using moments about the top platform.

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Certain varieties of tools amplify forces by using moment arms.

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