Light visible 11-14

This collection explores visible light, in particular colour, suitable for ages 11-14.

About visible light: The visible spectrum is the portion of the electromagnetic spectrum that is visible to the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light. A typical human eye will respond to wavelengths from about 390 to 700 nm. In terms of frequency, this corresponds to a band in the vicinity of 430–770 THz.

Resources in this collection:

• Exoplanet Atmospheres: In this activity developed by the Institute of Physics, students use simple diffraction gratings to observe the spectra from different sources, and deduce how scientists can work out which chemicals are present in an exoplanet’s atmosphere.
• Light and Optics Teacher Resource and Class Activities: This teacher guidance from NASA describes colour and light activities that can be used with students from Key Stage Two to Four. Using lenses, prisms and mirrors students create telescopes, periscopes, microscopes and kaleidoscopes. Other activities include finding focal length and understanding reflection, refraction and diffraction. The resource shows levels corresponding to the American school system but the range of activities are suitable for primary and secondary students in the UK.
• Light Survey: This is a practical activity from Virtual Maths where students collect information to be used in a data handling investigation. Students will need to have access to light meters, which are used to measure light readings in natural and artificial conditions at 1m² intervals. These readings are repeated and students take the average measurement.
  
  Readings are plotted onto a graph and the results compared against expected light levels. A table, which shows some general guidelines for lighting levels in different spaces, is available for further investigation or discussion.
• Seeing Pink Elephants: This resource will let students see pink elephants. 
  
  When the human eye is exposed to one colour for a relatively long period of time, the cone cells will become saturated with that colour. Once the eye is exposed to a broad range of colours again, the brain will pick up weaker signals from that colour and an image with that colour missing will be formed.
• The Earth's Atmosphere - Why is the Sky Blue? This Teaching Astronomy and Space video, from the Institute of Physics (IOP), Teachers TV and the Science and Technology Facilities Council (STFC), helps to explain the answer to a simple question: why is the sky blue? 
  
  Using a light source, a beaker of water and a few drops of milk, students can see how the milky water scatters blue light. This effect happens in the earth's atmosphere and the scattered blue light is seen as a blue sky. This is called Rayleigh scattering.
  
  It also shows that the transmitted light is red in colour and explains why sunsets sometimes appear red.