yr 8 science

• Refraction of light is the change in the direction of light as it passes from one medium to another.
• A light ray refracts whenever it travels at an angle into a medium of different refractive indices
• Light is a wave which transfers energy from one place to another.
• Objects like candle flames, electric lamps and the sun radiate (give out) light directly into our eyes.
• Other objects are only visible when light is reflected off them into our eyes e.g. we can only see the moon when the sun’s light is reflected from it.
• Look at the picture of Andy Robertson in his Liverpool kit. All of the colours of the visible spectrum are absorbed by his kit except red, which is reflected.
• At 90 degrees to the plane mirror a broken line is drawn which is called the normal
• Angle of Incidence = Angle of Reflection i = r
• Optical fibres are long thin strands of flexible glass
• colour order for reactions: red orange yellow green blue indigo violet
• White light can be split up into the seven colours of the visible spectrum using a triangular prism.
• Red light has the largest dispersion angle and violet light has the smallest
• The three primary colours of light are Red, Green and Blue.
• The three primary colours can be mixed together to produce the secondary colours red +green= Yellow , blue + green= Cyan and red+blue=Magenta.
• Red + Green = Yellow Red + Blue = Magenta Green + Blue = Cyan
• triangular prism is used to reflect all the spectrum of light
• A beam of light consists of many rays travelling together. The rays can travel in three ways: Parallel Converging Diverging