Science:Math Exam Resources/Courses/MATH102/December 2017/Question 08

MATH102 December 2017
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Question 08

A freshly laid egg has a temperature of $40$ degrees, and the temperature outside is $10$ degrees. After ten minutes ($t=10$ ), the temperature of the egg is $25$ degrees. What will the temperature be after $10$ more minutes ($t=20$ )? Assume the system obeys Newton’s Law of Cooling. That is, the rate of change of the temperature of the egg is proportional to the difference in temperature between the egg and the outside. Justify your answer.

Hint: you can find an exact answer with minimal calculation (and, of course, no calculator).

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