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Homework Help: Urgent: Finding time of death (without using calculus)

  1. Jan 16, 2006 #1
    I need help from this as soon as possible.
    My teacher has given me 2 equations and I need to use them to estimate the time of death of a discovered corpse.
    1.[tex] \frac {\Delta T_{1}}{\Delta t} = -k_{1}(T_{1} - T_{2}) [/tex]
    2.[tex] \frac {\Delta T_{2}}{\Delta t} = -k_{2}(T_{2} - T_{1}) [/tex]
    I think since the air temperature remains relatively constant, only equation 1 is needed.
    My problems: do i simply solve for delta t? Note: the k value does not matter in this case because we only need to know the physics behind these equations, and are not actually solving a question
  2. jcsd
  3. Jan 16, 2006 #2


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    Homework Helper

    Please post the complete problem statement.
  4. Jan 16, 2006 #3
    there is no actual problem because my teacher only wants us to explain how the above equations can be used in criminological applications to estimate the time of death of a discovered corpse. But I really don't know what we are solving for in this case. I tried researching on the internet but all the equations given uses calculus. My teacher wants us to use these equations, not differential calculus.
  5. Jan 16, 2006 #4
    perhaps you can tell use what these quantities are: T1 and T2 and k1 and k2...withot meaning to these variables we can not help you at all...you mention temperature...but which is temperature

    TO give you a start on answering your question...anything over dt usually means a change in quantity over time ...for example one can say

    dC/dt is a change in concentration over time.
  6. Jan 16, 2006 #5
    T1 is the temperature of substance 1 (i think that should be the temperature of the corpse), T2 should be the temperature of the air. k1 and k2 are constants which depend on the heat absoprtion propertiies of the substances.
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