Building Brick Questions Flashcards
(53 cards)
What is the difference between conductors and insulators?
Conductors are materials that are good at transferring thermal energy, insulators are not.
Which materials are the best conductors? Why?
Metals are the best conductors. This is because delocalized electrons move through the material faster transferring thermal energy.
Which materials are the best insulators?
Non-metals are the best insulators. Especially materials with air pockets in.
What is thermal conductivity?
Thermal conductivity is a measure of how good a material is at transferring thermal energy.
How does thermal conductivity relate to rate of energy transfer?
The higher the thermal conductivity, the faster the rate of energy transfer.
How does thickness of an insulator effect rate of energy transfer?
The thicker an insulator, the lower the rate of energy transfer.
Which objects emit and absorb infrared radiation?
All objects will emit (give out) and absorb (take in) infrared radiation.
Objects of which colour are best at absorbing and emitting radiation?
Dark, matte objects are the best absorbers and emitters of radiation.
Objects of which colour are best at reflecting radiation?
Shiny, light coloured objects are the best reflectors of radiation.
How does temperature relate to the amount of infrared radiation emitted?
The higher the temperature, the more infrared radiation is emitted (given out).
What is blackbody radiation?
Blackbody radiation is radiation emitted by a body that absorbs all the radiation incident on it (all radiation that hits it).
How does infrared radiation increase the temperature of objects?
If an object absorbs more infrared radiation than it emits, it’s temperature will increase.
How does the mass of an object affect the amount of energy needed to heat is?
The larger the mass of an object, the more energy is needed to increase its temperature.
Give five different methods of heating a home.
Electric heaters, gas heaters, gas-fired central heating, oil fired central heating and solid-fuel stoves.
Give five different methods of insulating a home.
Loft insulation, cavity wall insulation, double-glazed windows, aluminium foil behind radiators and external walls made from thicker bricks with a lower thermal conductivity.
What is cavity wall insulation?
Cavity wall insulation is insulation material that is used to fill the cavity between the two layers of bricks of an external wall of a house
What is the specific heat capacity of a material?
The specific heat capacity of an object is the amount of energy needed to heat 1kg of a material by 1°C.
What is a system?
A system is an object or group of objects?
What are the six energy stores?
Energy can be stored as: Chemical, Gravitational Potential, Kinetic, Elastic Potential, Thermal, and Internal.
What are four methods of transferring energy between stores?
Energy is transferred by heating, by waves, by electric current, or by a force moving an object.
What is the law of conservation of energy?
Energy can be transferred usefully, stored or dissipated, but cannot be created or destroyed.
What is a closed system?
A closed system is a system is a system where no energy can be transferred into or out of the system.
How does the energy in a closed system change during an energy transfer?
The total energy of a closed system is the same before and after the transfer of energy.
What is work done (in Physics)?
Work done on an object is the amount of energy transferred to the object by a force acting over a distance.
