newtons law of cooling (1 Viewer)

[hatty]

can someone plz explain 2 me what this is about?

in my next maths test, the teacher is going 2 ask a specific question on newtons law of cooling, does n e 1 have n e idea wut she mite possibly ask?

cheers

 

[Grey Council]

what part of it don't you understand?

If you have the coroneos 3u book, it covers this awesomely. Explanations, questions, etc.

 

[wogboy]

If you have an object at a temperature T and the room temperature is R, then the rate at which the object cools (if T > R) or heats (if T < R) is proportional to the difference between T and R.

In mathematical form:

dT/dt = k*(R-T)
(T = temp of object, t=time, R = room temp, k= some constant)

if you solve the above equation for T (by integration) you'll always get an answer in the form which describes the temperature of the object T, at time t:

T = R + (T0 - R)*e^(-kt) (T0 is the initial temperature). You should be able to see that when t=0, T=T0 (initial temp) and as t -> infinity, T -> R.

[Edit] Some useless extra trivia in case you're interested: the constant k depends on the thermal conductivity, mass, surface area, and specific heat capacity of the object.

 

[hatty]

thanks alot wogboy