Energy- Conduction & Radiation Flashcards
_______ are the best conductors with a ____ energy transfer and ___-_______ are insulators with a ___ energy transfer.
Metals are the best conductors with a high energy transfer and non-metals are insulators with a low energy transfer.
Convection is the movement of ____ in ______. The _________ in the fluid become less
dense when hot, rise and float. When ____ the particles become denser and sink.
Convection is the movement of heat in fluids. The particles in the fluid become less
dense when hot, rise and float. When cold the particles become denser and sink.
All hot objects radiate heat in the form of _____. There is no need for particles.
All hot objects radiate heat in the form of waves. There is no need for particles.
Houses are _________ to prevent energy loss and save ______ _________ and _____.
Houses are insulated to prevent energy loss and save energy resources and money.
Double glazing prevents heat loss because they have a trapped layer of ___ so both
___________ and ___________ cycles are disrupted.
Double glazing prevents heat loss because they have a trapped layer of gas so both
conduction and convection cycles are disrupted.
Insulating panels are made of a foam and coated with foil, this reduces r_________,
c__________ and c___________.
Insulating panels are made of a foam and coated with foil, this reduces radiation,
conduction and convection.
All objects ____ and ______ radiation, the hotter it is, the ____ it gives out.
All objects emit and absorb radiation, the hotter it is, the more it gives out.
The earth’s temperature depends on r________ from the s__.
The earth’s temperature depends on radiation from the sun.
__________ the number of layers of insulation _________ thermal transfer so the
temperature loss is less.
Increasing the number of layers of insulation decreases thermal transfer so the
temperature loss is less.
Materials with trapped layers of ___ are good insulators because heat does not
transfer well between ______ and _____.
Materials with trapped layers of air are good insulators because heat does not
transfer well between solids and gases.
the ______ the thermal conductivity of a material, the higher the ____ of energy transfer by conduction across the ________
the higher the thermal conductivity of a material, the higher the rate of energy transfer by conduction across the material
what are the two layers of a modern house
external - brick wall
internal - breeze block
what is found between these two walls
a cavity
what do builders pack the cavity with to avoid heat loss
insulating material which has a very low thermal conductivity
required practical: thermal insulators
- place a small beaker inside a larger beaker
- boil a kettle and pour 80cm^3 of water into the small beaker
- place a cardboard lid on top - cut a hole for the thermometer
- place thermometer in and end=sure bulb of thermometer is in hot water
- record the starting temp and start stop watch
- record temp of water every 3 minutes for 15 minutes
- repeat using same volume of water but add an insulating material - test a range of different insulators
- record results in a table
