Engineering Board Exam Reviewer · Applications: Cooling, Heating, and Mixture Problems · medium

A body is found at 9:00 a.m. with a temperature of 31° C. At 11:00 a.m. it is 26° C. The room is kept at 20° C and normal body temperature is 37° C. How many hours before 9:00 a.m. did death occur?

  1. 2.4 h
  2. 2.01 h
  3. 1.44 h
  4. 0.72 h

Answer

C. 1.44 h

Solution

T-20=Aekt with t measured from 9:00. At t=0: A=11; at t=2: 6=11e2k k= 12 611 -0.3030. At death T=37: 17=11ekt t= (17/11)/k -1.44. Death occurred about 1.44 hours before 9:00 a.m.

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