# physics

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In an electrically heated home, the temperature of the ground in contact with a concrete basement wall is 13.0 oC. The temperature at the inside surface of the wall is 21.1 oC. The wall is 0.19 m thick and has an area of 8.3 m2. Assume that one kilowatt hour of electrical energy costs \$0.10. How many hours are required for one dollar's worth of energy to be conducted through the wall?

• physics -

Assuming your heat loss is correct, you lose 0.601.5 kw-h per hour, and that costs you 6.02 cents. That will cost you a dollar's worth of electricity in
100/6.02 = 16.6 hours

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