Reducing Unwanted Energy Transfers
This lesson covers:
- How to reduce unwanted energy transfers
- Different ways insulate your home
- How to reduce friction
Which type of heat loss do foam seals around windows and doors help to minimise?
(Select all that apply)
Heat loss by convection
Heat loss by conduction
Heat loss by radiation
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Which of the following are features of a house which help to reduce heat loss by conduction?
(Select all that apply)
Cavity walls
Double glazed windows
Foam seals around windows
Walls made of a material with low thermal conductivity
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What is the purpose of putting insulating foam in cavity walls?
To minimise loss of heat by radiation
To minimise air convection currents
To strengthen the wall
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Single vs double glazing
conduction / convection / radiation / one / two / three
Single glazed windows only have pane of glass, whereas double glazed windows have panes of glass. In both cases, the panes of glass reduce heat loss by .
The added benefit of double glazing is that there is a small air gap between the two panes of glass, which minimises (as air is a poor conductor of heat).
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What is being described by the following sentence?
"The resistance that an object encounters when moving across a solid, or moving through a liquid"
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Which of the following helps to reduce friction between two surfaces?
Sand
Lubricant
Rubber
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mass / friction / fuel / streamlined
Fast moving vehicles like cars and planes have a shape to reduce from air resistance. This allows them to use less .
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Why does cavity wall insulation contain pockets of trapped air?
Air is a good insulator
Air is a good conductor
Air is a good radiator
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Double glazing costs £900 to install. It saves £50 a year in fuel costs.
How long will it take to recoup (make back) the initial costs?
years
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