document.write( "Question 93978: When a cold yam is put into a hot oven to bake, the temp. of the yam rises. The rate, R,at which the temp. rises is governed by Newton's Law of Heating, which says that the rate is proportional to the temp. difference between the yam and the oven. If oven is 350 degrees and the yam is H degrees. Which can be used to model the temp. of the yam. Is it R=kh-350 or R=k(350-H) or R=k(H-350)? \n" ); document.write( "
Algebra.Com's Answer #68524 by bucky(2189)\"\" \"About 
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When the yam is put into the oven, it is cooler than the oven. Therefore, to get a positive
\n" ); document.write( "answer to the difference in the temperatures, we have to subtract the temperature of the
\n" ); document.write( "yam from the 350 degree temperature of the oven. Therefore, the temperature difference
\n" ); document.write( "should be written as (350 - H)
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\n" ); document.write( "The constant of proportionality k then multiplies that temperature difference. So the rate
\n" ); document.write( "R is given by the equation:
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\n" ); document.write( "\"R+=+k%2A%28350+-+H%29\"
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\n" ); document.write( "The correct answer to your problem is the middle answer of the three you listed. The first
\n" ); document.write( "answer is incorrect because k does not multiply both the 350 and the H as it does in
\n" ); document.write( "our answer. And the last answer is incorrect because k will be positive and the difference
\n" ); document.write( "of H - 350 will be negative since the yam is cooler than the oven. So in multiplying
\n" ); document.write( "the constant k times (H - 350) you will get a negative answer, which indicates the rate is
\n" ); document.write( "negative ... meaning the yam is cooling off instead of heating up. Obviously not correct.
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\n" ); document.write( "Hope this helps you to analyze the problem.
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