Visible light: Waves: Physics: GCSE (9:1)

• Visible light spectrum

  A spectrum of colour within the electromagnetic spectrum

  
• Colours in order of increasing frequency

  Red, orange, yellow, green, blue, indigo, violet

  
• Absorption of light on a surface

  When light is absorbed by a surface, the energy of the wave is transferred to the particles in the surface

  
• Opaque surfaces


  Surfaces that absorb some wavelengths of light so they cannot be seen and reflect the rest
• Colour of an opaque surface

  Determined by which wavelengths of light are more strongly reflected
• White


  The colour an opaque surface will appear because all wavelengths of light are reflected equally

  
• Black


  The colour an opaque surface will appear when all wavelengths of light are absorbed

  
• Transmission of light

  When light is transmitted, the light continues to travel through the material

  
• Transparent materials


  Materials that transmit light with very little absorption

  
• Translucent materials


  Materials that transmit some light with some absorption

  
• Coloured filter


  Absorbs certain wavelengths of light and transmits other wavelengths

  
• White light on a coloured filter


  All colours are absorbed except for the colour of the filter