Dark, matt = GOOD radiation emitter, GOOD radiation aborber
Light, shiny = POOR radiation emitter, POOR radiation absorber, GOOD reflector of INRARED RADIATION
THE HIGHER THE TEMPERATURE = THE MORE ENERGY EMITTED AS INFRARED RADIATION
KENETIC THEORY = OBJECTS ARE MADE UP OF PARTICLES THAT ARE CONSTANTLY MOVING
SOLIDS: Particles VIBRATE about fixed positions. Solids have fixed shape. Add energy
LIQUIDS: Partiles move around, stay close together. Liquids can flow.
The amount of energy a particle has is related to temperature of material
Methods of transferring energy
- Particles in solid given more energy and vibrate more.
- Collide with neighbouring particles, then they vibrate more
Energy spreads through solid.
- Particles in liquid or gas given more energy, move faster and spread out.
- Density is lower so hot material rises
- Replaced by cool material, so convection current is set up
Rate of energy transfer
Evaporation takes place faster when:
- Temperature is higher
- Large surface area in contact with air
- Wind blows water vapour away
- Flask is made of INSULATING MATERIAL, slows energy transfer from hot liquid to outside by CONDUCTION.
- Vacuum between two layers, so energy cannot be transferred by CONVECTION.
- Silver coating reduces amount of enery transfer by RADIATION.
STEP-UP TRANSFORMERS = INCREASES voltage, DECREASES current
- Pylons are form of visible pollution.
- People can be injured if climbing pylons, less likely to be injured by buried cables
- Burying cables is more expensive
- More difficult to make repairs
- Digging trenches damages habitats temporarily