The inside temperature of a house is 65 °F. When the temperature outside the house is 35 °F, the furnace supplies 100 joules per hour to keep the inside of the house warm. If the temperature outside the house increases to 50 °F, then what is the fuel consumption of the furnace? Assume the house loses heat through conduction only.

Question

Quizplus · Accepted Answer

The rate of heat loss through conduction is proportional to the temperature difference between inside and outside. Initially, the difference is 30°F (65°F - 35°F) and the furnace supplies 100 joules per hour. When the outside temperature is 50°F, the difference is 15°F (65°F - 50°F), which is half of the initial difference. Therefore, the furnace needs to supply half the initial energy, which is 50 joules per hour.

The Inside Temperature of a House Is 65 °F