Math 111)0
Homework 24
13 November, 2013
Key
Name:
1. (12 points) Newton’s law of cooling (or warming) states that the rate of change of tein—
perature u of an object is proportional to the temperature difference between the obcct
and its surroundings. That is,
=k(u—T)
where T is the constant. temperature of the surroundings and k is sonic constant.
Suppose an object at 00 C is placed in a room where the temperature is 30° C. If the
temperature of the 01) ject is 12° C after 1 hour, how long will it take for the object to
reach 27° C?
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1)0 used to estunate tune of death (though the
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estimate is likely to be quite rough). Suppose a corpse is (liscovered at 110011 ill a
F 10011) and at that time the body temperature is 96.10 F. If at 1:00 PM the body
F, use Newton’s law of cooling to estimate time tine of (heath. (You
temperature is
may assume that time body temperature was 98.6° F when alive.)
2. (12
points)
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