Light and Dark Cross Curriculum Project

Many subjects in the National Curriculum include the study of light and dark – the most obvious being science. However the topic can be effectively used as a foundation for literacy, numeracy, art, history and RE lessons. In RE specifically, the topic of light can effortlessly lead into an investigation into various Festivals of Light, such as Hanukkah and Diwali.

Ways of thinking about light

From the time of the ancient Greeks, people have thought of light as a stream of tiny particles. After all, light travels in straight lines and bounces off a mirror much like a ball bouncing off a wall.

The idea of the light wave came from Christian Huygens, who proposed in the late 1600s that light acted like a wave instead of a

stream of particles. In 1807, Thomas Young backed up Huygens’ theory by showing that when light passes through a very narrow opening, it can spread out and interfere with light passing through another opening. Young shone a light through a very narrow slit. What he saw was a bright bar of light that corresponded to the slit. But that was not all he saw. Young also perceived additional light, not as bright, in the areas around the bar. If light were a stream of particles, this additional light would not have been there. This experiment suggested that light spread out like a wave. In fact, a beam of light radiates outward at all times.

Albert Einstein advanced the theory of light further in 1905. Einstein considered the photoelectric effect, in which ultraviolet light hits a surface and causes electrons to be emitted from the surface. Einstein’s explanation for this was that light was made up of a stream of energy packets called photons. Modern physicists believe that light can behave as both a particle and a wave, but they also recognise that either view is a simple explanation for something more complex.

<--- The article continues for users subscribed and signed in. --->