You need to have JavaScript enabled to view this video clip.

Description

The presenter explains that the only things you can see are light sources or reflectors, which are objects that reflect light. If you were a reflective object, you could be seen by someone with a light source, but you wouldn't be able to see any reflective objects. However, with a light source, you could see reflective objects as well are being visible yourself.
This clip is from:
First broadcast:
17 May 2007

Classroom Ideas

Students could try and determine experimentally why reflective jackets use specific materials, by testing a variety of different materials and deciding which reflects the most light. This could be expanded and linked into a possible road safety project. As well as considering reflectivity, discuss with student the angle of reflection and how this might relate to the perceived lightness or dimness of light.

This clip also features in: