Energy

• Light travels in straight lines
• The 8 stores of energy are thermal, kinetic, electrical, elastic, magnetic, chemical, gravitational and nuclear.
• The conservation of energy is a law which states energy cannot be created or destroyed.
• Radiation is absorbed by matte, black surfaces. Radiation is reflected by silver shiny or white surfaces.
• Thermal equilibrium occurs when all objects have been left in a room for long enough that they become at the same temperature.
• Convection is when a fluid is heated, the particles gain kinetic energy and move apart. This region of fluid becomes less dense, transferring the thermal energy with it.
• Images in plane mirrors are laterally inverted.
• The angle of incidence is always equal to the angle of reflection.
• Refraction is an effect that occurs when waves travel into different substances.
• Reflection is when light hits a surface and it rebounds.
• Sound waves are longditudinal.
• Compression is when the molecules are squeezed together (higher pressure) and rarefraction is when the molecules are spread out (lower pressure).
• Sound waves travel fastest through dense solids because the vibra are easier to pass on when the particles are closer together.
• Red, blue and green are th primary colours of light.
• Yellow, magenta and cyan are the secondary colours of light
• All the colours of light together make white
• Sound is caused by vibrations
• Sound is carried by sound waves