WEBVTT

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So we saw that a conservative
force is path independent.

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And we also had
examples of forces

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which are path dependent, if
you have a path 2 and path 1.

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And the work done
is path dependent.

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So that means for each path we
will get a different answer.

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Then we call this force
F, be denoted by nc,

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is called nonconservative.

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And again, we see that
friction is the best example

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of a nonconservative force.

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And if we go again for
a nonconservative work,

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if we integrate from
the initial point

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to the final point, for
instance, on our path

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1 of this nonconservative force,
so if we integrate this way

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and if we reverse the
interval, and so we go back

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from the final point to the
initial point on path 2,

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that these integrals will not
be equal to the negative view

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of each other because
the quantities are

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different for the different
paths, in general,

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and so this is nonzero.

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And in fact, that's the property
of nonconservative forces,

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that the work done
around a closed

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path for a nonconservative
force is not equal to zero,

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in general.

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There may be one
specific closed path

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in which that answer is zero.

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But in general, it's nonzero.