Energy Transfer

Energy Transfer

Conduction
1. Needs particles to work.
2. Works quickest in solids.
3. Particles are heated and then start vibrating they collide with the particle next to them and pass on kinetic energy.
4. Metals being heated
  1. Metals contain free electrons that can move freely
  2. Metals are excellent conductors because of this.
Convection
1. Needs particles to work
2. Works in liquids and gases
3. The particles are heated and become less dense. Because they become less dense they rise.
4. The particles then hit cooler air or liquid and cool down, they become more dense and therefore fall
5. Convection current
Infrared Radiation
1. Does not need particles
2. Can travel through a vacuum
3. All objects emit or absorb infrared radiation
4. Dark, matt surfaces are good emitters and good absorbers
Evaporation
1. Particles at the surface of a liquid have enough energy to leave.
2. The average kinetic energy decrease because they have less kinetic energy. The temperature of the liquid also decreases.
3. Factors that increase rate of evaporation: Increase temperature, increase draught, increase surface area, decrease humidity and decrease strength of intermolecular forces
Larger surface area=faster rate of heat transfer.
Energy cannot be created or destroyed
Bigger temperature difference=faster rate of energy transfer

Resource summary

	Created by robynhattieemily over 11 years ago