Monday

July 28, 2014

July 28, 2014

Posted by **Samuel** on Friday, April 26, 2013 at 6:48pm.

- math/physics -
**Count Iblis**, Friday, April 26, 2013 at 7:04pmThe amount of heat per unit time that leaks out of the house is approximately proportionate to difference between the inside and outside temperature. The thermostat will make sure that as much heat is produced by the heating as is leaking away, so that thee temperature stays constant on average.

So, if the thermostat is left at 68 F all day, the total amount of heat used per day will be some constant c times (68-15), while if it is set at 50 F for half a day and 68 for the other half, you'll use

1/2 c (50-15) + 1/2 c (68-15)

per day.

c (68 - 15) = 53 c

1/2 c (50-15) + 1/2 c (68-15) =

44 c

44c/(53 c) = 0.83

So, you save 17%

**Related Questions**

math,help - the problem says: one day, the temperature at 2:00AM was 44 degrees ...

Thermochemistry please - I really need help on this problem...

math - The temperature on one day in January for Phoenix, AZ, is 59 degrees ...

Math 116 - 1.IN a given training week, a swimmer completes 1/4 mile on day one, ...

chemistry - 3.6 g of a hydrocarbon fuel is burned in a calorimeter that contains...

6th grade math - Which expression could you use to find the measure of an angle ...

Earth Science - How many hours of daylight occur at the following locations on ...

math - find the angle that is coterminal to 525 degrees and lies between 0 ...

Math - One angle of an isosceles triangle is 28°. What are the other 2 angles? (...

trig - on the same set of axes: (0 degrees is greater than or equal to x and x ...