In this activity, students choose two types of transparent substance. They then enter the angle of the incident ray in the spreadsheet calculator, and the angle of the refracted ray is calculated for them.

By the end of this activity, students should be able to:

  • use a spreadsheet calculator to calculate the angle of refraction
  • define the terms ‘incident ray’, ‘refracted ray’ and ‘normal’
  • recall the refractive index values for water and air
  • describe how the amount of refraction (bending) depends on the refractive index of the two substances light is passing between
  • describe the direction that light bends when it passes into a substance with a higher refractive index
  • describe the direction that light bends when it passes into a substance with a lower refractive index
  • find the maximum angle possible before all light is totally internally reflected when light travels from a more-dense substance (such as water) into a less-dense substance (such as air).

Download the Excel file (see link above) for the Angle of refraction calculator.

Download the Word file (see link above) for:

  • introduction/background notes
  • what you need
  • what to do
  • student record sheet.

Nature of science

Scientists often use models and spreadsheets to help with calculations that predict things such as how much light will bend as it passes from one substance into another.

Useful links

This simulation provides opportunity for further, more in-depth investigations of how light behaves as it passes from one substance into another.
http://phet.colorado.edu/en/simulation/bending-light

    Published 26 April 2012