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Cooling process - Exponential functions

  • Thread starter Svensken
  • Start date
  • #1
29
0

Homework Statement



Hello i am doing a cooling experiment and i want to know the following:

y=28.49e^(-0.03890*800) +26.51 (note the 26.51) is not part of the exponential.

What is y? and I was wondering whether this would go ever go through the x axis?

Thanks people!

Homework Equations



T=T(initial)*e^(-kt)+T(room)

The Attempt at a Solution



I have been putting the info into my calculator and i just cant seem to be able to graph it (TI-84) and from my knowledge of exponentials i don't think that an exponential like this can be below the x axis, but i may very well be wrong.

Thanks again
-Svensken
 

Answers and Replies

  • #2
rock.freak667
Homework Helper
6,230
31
When y=0

Aekx+B= 0 ⇒ ekx=-B/A

and ekx is never less than zero for all values of x. Thus it does not cross the x-axis.
 
Last edited:
  • #3
29
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Thanks mate!
 

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