Thermodynamics - heat transfer calculation

[urgent]

Homework Statement

to conserve heat energy in a home, R=2.8 Pink Batts are replaces by R=3.2 Pink Batts. calculate the percentage increase in reduction of heat loss per 1.0m^2 of wall when the temperature difference is 15degrees celsius.

Homework Equations

P=A(Th-Tc)/ R

The Attempt at a Solution

i tried to do this:
1(15)/ 6= 2.5
i do not think this is the right answer, it's a question form my last year's exam paper and i really need to know this for my exam in 2 days..please help =] thx

 

[anathema]

Hello, as a scientist, I can provide you with the correct solution to your problem. Firstly, let's define the variables in the equation you provided. P represents the rate of heat loss, A represents the area of the wall, Th represents the temperature inside the house, Tc represents the temperature outside the house, and R represents the thermal resistance.

Now, let's calculate the percentage increase in reduction of heat loss per 1.0m^2 of wall when the temperature difference is 15 degrees Celsius for R=2.8 Pink Batts and R=3.2 Pink Batts.

For R=2.8 Pink Batts:
P= 1(15)/2.8= 5.36

For R=3.2 Pink Batts:
P= 1(15)/3.2= 4.69

Now, let's calculate the percentage increase in reduction of heat loss:
(5.36-4.69)/5.36 x 100= 12.5%

Therefore, by replacing R=2.8 Pink Batts with R=3.2 Pink Batts, there is a 12.5% increase in reduction of heat loss per 1.0m^2 of wall when the temperature difference is 15 degrees Celsius. I hope this helps and good luck on your exam!