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Let's consider the
motion of an object that

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is under the action of a force.

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So we have some force that's
acting on this object.

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And we have a little
displacement ds.

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So this is a small
displacement of the object.

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Then we know that
the small amount

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of work done by the action
of this force is F.ds.

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And the rate of doing work,
so let's now introduce

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the concept of power, which
is the rate of doing work.

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That is, F.ds over dt.

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And ds dt is just the
velocity of the object.

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So we see very
simply that when we

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talk about power, and sometimes
people use the symbol p,

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although we can also talk
about pressure and momentum,

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so it's a little bit tricky.

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But here, the power
is F.v. And power

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is a concept that will appear
in many different settings.