SOLUTION: A thermometer reading 35 degrees F is brought into a room with a constant temperature of 75 degrees F. If the thermometer reads 42 degrees after 5 minutes, what will it read after

Algebra ->  Trigonometry-basics -> SOLUTION: A thermometer reading 35 degrees F is brought into a room with a constant temperature of 75 degrees F. If the thermometer reads 42 degrees after 5 minutes, what will it read after       Log On


   

Question 947676: A thermometer reading 35 degrees F is brought into a room with a constant temperature of 75 degrees F. If the thermometer reads 42 degrees after 5 minutes, what will it read after being in the room for 8 minutes? Assume the cooling follows Newton's Law of Cooling: U=T+(Uo-T)e^kt
Answer by josgarithmetic(39616) About Me  (Show Source):
You can put this solution on YOUR website!
Many people may not know what the variables mean.

Most of the way down in the article:
http://en.wikipedia.org/wiki/Convective_heat_transfer#Newton.27s_law_of_cooling

Refering to the equation you presented,
U, temperature after time t
T, temperature of the environment
Uo, temperature initially
t, amount of time passage.
The exponent should be kt.

The data in problem description:
highlight_green%2842=75%2B%2835-75%29e%5E%28k%2A5%29%29;
Check to see that each given value is in the correct place for its meaning. This equation will allow you to solve for k.

Once k is found, you have a model more like:
U=75%2B%2835-75%29e%5E%28k%2A8%29
but now you would have found k and can evaluate U.