College Physics

In this problem you will estimate the heat lost by a typical house, assuming that the temperature inside is T(in) = 20 degrees celcius and the temperature outside is T(out) = 0 degrees celcius. The walls have fiberglass insulation, which dominates the heat conduction properties of the wall So we can consider the wall to have a thermal conductivity of k(wall) = 0.048 W/m/K
. We will take the thickness of the walls and ceiling to be L(wall) = 12 cm. Assume that the house is a cube of length L = 9.0 m on a side. Assume that the roof has very high conductivity, so that the air in the attic is at the same temperature as the outside air. Ignore heat loss through the ground.

a)What is H, the total rate of energy loss due to heat conduction for this house?

b)Let us assume that the winter consists of 150 days in which the outside temperature is 0*C on average. This will give the typical number of "heating degree days" observed in a winter in Vancouver. Given that heating oil has an energy content of 35 MJ per litre when burned, how much oil will be needed to supply the heat lost by conduction from this house over a winter? Assume that the heating system is 75% efficient.

  1. 👍 0
  2. 👎 0
  3. 👁 146
asked by Becky

Respond to this Question

First Name

Your Response

Similar Questions

  1. College physics

    In this problem you will estimate the heat lost by a typical house, assuming that the temperature inside is T(in) = 20 degrees celcius and the temperature outside is T(out) = 0 degrees celcius. The walls have fiberglass

    asked by Jacob on November 6, 2014
  2. Physics

    In a house the temperature at the surface of a window is 22.3 °C. The temperature outside at the window surface is 2.82 °C. Heat is lost through the window via conduction, and the heat lost per second has a certain value. The

    asked by Anonymous on August 22, 2015
  3. physics

    In a house the temperature at the surface of a window is 20.1 °C. The temperature outside at the window surface is 2.72 °C. Heat is lost through the window via conduction, and the heat lost per second has a certain value. The

    asked by Anonymous on November 17, 2014
  4. physic

    In a house the temperature at the surface of a window is 25 ¡ãC. The temperature outside at the window surface is 5.0 ¡ãC. Heat is lost through the window via conduction, and the heat lost per second has a certain value. The

    asked by firous on March 31, 2010
  5. finance

    can anyone help me set up this problem bc im totally lost.... if a house = $125,000 you want to buy this house in 10 years its expected to increase 5% a year over a 10 year period assuming you can earn 10% annually on investment.

    asked by nneka on September 11, 2008
  6. Chemistry

    Combustion of natural gas (primarily methane) occurs in most household heaters. The heat given off in this reaction is used to raise the temperature of the air in the house. Assuming that all the energy given off in the reaction

    asked by Lana on January 14, 2016
  7. Science-Chemistry

    A 5.00 g sample of Al pellets (specific heat = .89 J/g degrees c) and a 10.00 g sample of Fe pellets (specific heat = .45 J/g degrees c) are heated to 100.0 degrees C. The mixture of hot Fe and Al is then dropped into 97.3 g of

    asked by Niclas on October 1, 2007
  8. CHEM

    A 5.00 g sample of Al pellets (specific heat = .89 J/g degrees c) and a 10.00 g sample of Fe pellets (specific heat = .45 J/g degrees c) are heated to 100.0 degrees C. The mixture of hot Fe and Al is then dropped into 97.3 g of

    asked by Charlie on October 1, 2007
  9. Physics- LOST!

    If the air temperature is the same as the temperature of your skin (about 30.0 C), your body cannot get rid of heat by transferring it to the air. In that case, it gets rid of the heat by evaporating water (sweat). During

    asked by Jamie on December 3, 2007
  10. math

    1 litre of coffee at 80oC need to be cooled to 40oC. Assuming that all the ice melts and no heat is lost to the environment. Take the specific heat capacity of coffee to be 4200J/kgK, density of coffee to be 1000kg/m3 and latent

    asked by tony on March 13, 2017

More Similar Questions