What is the energy consumption at a different temperature?

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AI Thread Summary
The discussion revolves around calculating energy consumption and leakage in a heated house during winter. For part (a), the average energy leakage through the walls was determined to be 13,250 watts based on a 53 kWh expenditure over four hours at a temperature difference of 20°C. In part (b), the user seeks to calculate the electricity consumption if the house temperature was raised to 27°C, noting that energy transfer is proportional to the temperature difference. They realize that using the ratio of energy to temperature difference can help find the required energy consumption. The conversation highlights the importance of understanding temperature differences in energy calculations.
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Homework Statement



During 4 hours one winter afternoon, when the outside temperature was 4° C, a house heated by electricity was kept at 24° C with the expenditure of 53 kwh (kilowatt·hours) of electric energy.
(a) What was the average energy leakage in joules per second (watts) through the walls of the house to the environment (the outside air and ground)?
13250 watts

(b) The rate at which energy is transferred between two systems due to a temperature difference is often proportional to their temperature difference. Assuming this to hold in this case, if the house temperature had been kept at 27° C (77° F), how many kwh of electricity would have been consumed?
____kwh

Homework Equations



(a) power = work / delta time
energy transfer = work / delta time

(b) ?

The Attempt at a Solution




(a) First, I converted the 52 kwh to be 1.908e8 wsec
Then, I converted the 4hours to 14400 seconds
Doing so, I found the energy transfer to be 13250 watts for part a.

(b) For the second part I'm sure how to use the temperatures given to find the energy consumed
 
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What is the temperature difference in a) ? and in b)?.

energy leakage is proportional to temperature difference... use ratios...
 
delta t for a = 24-4 = 20

delta t for b = 27-4 = 23

correct?

so how do i use a ratio to get to the energy?
 
never mind i figured out to use E/T = E/T

just wasnt thinkin

thanks
 
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