Question

The window shades of rooms are pulled down so that a layer of still air is formed near the window to reduce the heat loss by

• A. Conduction
• B. Convection
• C. Radiation
• D. All

Answer 1

The correct option is B Convection

For heat insulation in a house,it is very important to prevent the heat loss by convection and conduction. To prevent loss of heat by convection , even the small opening in the window frame is closed by the weather stripping. To prevent loss of heat by conduction, the ceiling and the wall are covered with player of glass wool. (layers of glass wool are placed in between the plaster and ceiling or the outer walls of the house). The window shades of rooms are pulled down so that a layer of still air is formed near the window to reduce the heat loss by conduction since trapped air is a poor conductor of heat.