WEBVTT
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welcome to our first example video. Looking at the
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first law of thermodynamics. To begin with, we're
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going to look at this P V diagrams and evaluate
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the work done along the two different paths. One
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. And to that we have here just conceptually looking
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at this. You should remember that when we have
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work that is done at a constant volume, that
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work is zero. So work one is going to
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be equal to zero jewels, plus the work done
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along this path, which is going to be one
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Kill a pascal. That's the constant pressure multiplied by
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the change in volume, which is 500 minus 100
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cubic centimeters. So that's 400 cubic centimeters for work
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. Along the second path, we see that we're
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going to have a constant pressure of three Killah Paschal's
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over the same over the same change in volume,
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which means we have three Killah Pascal's multiplied by 400
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cubic centimeters, and then we have a constant volume
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. Step again means we will add zero jewels.
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So notice here that it took more work to do
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go along the second path than it took to go
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along the first path or Rather, it required more
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work from the system to follow the second bath than
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to follow the first path. So, uh,
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again, path dependence is important here with our work
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, we need to make sure we're keeping track of
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which path we're taking. And we can also begin
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to ask ourselves, Is there a most efficient path
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that we could take?