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Hey everyone, this is question number 44 from chapter 14.
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In this problem, we're given a copper pot of mass 0 .5 kilograms.
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It contains 0 .17 kilograms of water.
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Both of them are at 20 degrees celsius.
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And then an iron block of mass 0 .25 kilograms is dropped into the pot, and it is at 85 degrees celsius.
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So then we're asked to find, that's all of our givens, and we're asked to find the final temperature of the system, and we're told there's no heat loss.
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So again, we're having temperature changes, masses, so we should recognize q equals mc delta t as our go -to equation for this kind of question.
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And we're solving for final temperature, but we need to go ahead and define q for each one of the parts of the system, which would be the copper pot, the water inside the pot, and the iron block.
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So, q for the copper pot, let me draw a better q.
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Qc for copper pot is equal to mass, 0 .5 kilograms.
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C for copper is 390 joules per kilogram k.
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And then for delta t, we know that any change is to find us final minus initial.
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So we're going to see t is our final and minus our initial for the.
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The pot is 20 degrees c.
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Okay, so that's our equation for q of c.
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Now we can go on to q of the water inside the pot is equal to mass of the water, 0 .17 kilograms.
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For water, c is 4190, joules per kilogram k.
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And then our delta t again is going to be, for the water, starts at 20.
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So our final is t.
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We don't know that minus 20 degrees celsius which is our initial and then we can do q of the block which is equal to mass of the block 0 .25 kilograms c for iron is 470 and then our temperature is going to be our final t minus 85 degrees c so the same thing for every single one of them.
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Okay, so we have these three expressions.
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Now we can go ahead and multiply them out and simplify them, and we're told there's no heat transfers...