p1 summary

p1 summary

1. the transfer of energy by heating processes

   • kinetic theory can be used to explain different states of matter
   • u- values measure how effective materials are as insulators
   • the energy needed to warm 1 kg of a material by 1 degree Celsius is its specific heat capacity
   • solar panels use the suns radiation to warm water

2. factors hat affect the rate at which energy is transferred

   • all objects absorb and emit infrared radiation the temperature and colour of the surface affect how quickly this happens
   • conduction, convection, evaporation and condensation transfer energy and involve particles
   • convection transfers heat in liquids and gases conduction transfers heat most effectively in solid
   • the rate of reaction depends on the surface area, material, colour type of surface and the type of surface it is in contact with.

3. energy transfers, efficiency and electrical energy

   • the efficiency of a device is the useful energy out / the total energy in
   • energy can be transferred stored or dissipated it cannot be created or destroyed
   • electrical appliances carry out different energy transfers

4. generating and distributing electricity

   • the national grid distributes from power stations
   • energy from water (hydroelectricity) and wind turbines directly.
   • production of greenhouse gases pollution and flooding and waste materials.

5. waves communications and the universe

   • radio waves, microwaves, infrared, visible light are used for communication
   • waves are reflected this is how a image in a mirror is formed
   • sound waves are longitudinal waves the loudness depends on the amplitude and frequency