Conductive Heat Loss in a house

[plexxity]

Homework Statement

If only conductive heat loss was significant for a house, then by what percentage would you lower the heat loss if the temperature was reduced inside from 73°F to 67°F, when the outside temperature is 21°F? (Hint: Try using a ratio.)

Homework Equations

Unknown

The Attempt at a Solution

I do NOT want the solution just need to know what formula i should use to find the answer.

possibly a example problem but NOT the answer please, i want to learn how to do it.

 

[mgb_phys]

The heat loss is proportional to the temperature difference.
So as an equation you would write Power = k * (Tinside-Toutside)
The value of K would depend on your units for temperature, the material the house is made of and it's insulation - the important point is that k does not change.

Remember as well that you need T in absolute units.

 

[Dadface]

The heat loss is proportional to the temperature difference.
So as an equation you would write Power = k * (Tinside-Toutside)
The value of K would depend on your units for temperature, the material the house is made of and it's insulation - the important point is that k does not change.

Remember as well that you need T in absolute units.

But because the power is proportional to the temperature difference you can express the temperatures in Celcius as well as kelvin.Both give the same answer.

 

[plexxity]

Thanks you guys are awesome

 

[phys-unit]

Could someone give me the answer the this problem? I have a similar problem and need help.

 

[plexxity]

so what would the value of k be then? that's what i can't figure out.

 

[plexxity]

i have Power=k(19.4C-(-6.1C))

k isn't given in the problem?