P1 Heating houses

P1 Heating houses

1. Energy flow

   • Energy in the form of heat flows from a warmer to a colder body.
   • When energy flows away from a warm object the temperature of that object decreases

2. Measuring temperature

   • A thermogram uses colour to show temperature: hottest areas are white/yellow, coldest ares are black/dark/purple/blue
   • Heat is a measurement of internal energy. It is measured on an absolute scale

3. Specific heat capacity

   • All substances have a property called specific heat capacity which is; the energy needed to raise the temperature and measured in joules per kilogram
   • When an object is heated and its temperature rises energy is transferred
   • Energy transferred = mass x specific heat capacity x temperature change

4. Specific latent heat

   • It is the energy needed to melt or boil 1kg of the material and measured in joule per kg and differs for different materials and each of the changes of state
   • When an object is heated and it changes state energy is transferred but the temperature remains constant
   • Energy transferred = mess x specific latent heat