What is a bending pencil experiment? Why does a pencil during an experiment in water looks bent? The pencil appears to bend owing to refraction of light, when it passes through transparent materials. The light rays coming from the submerged part of the pencil appear bending as they leave the water.
Light rays are reflected and absorbed by opaque materials such as glass, air, water, oil and certain plastics, allow the light rays to pass through them. But in doing so they bend them to a greater or lesser degree.
Refraction occurs naturally. The stars not directly overhead are in different place from those they seem to be in, because the light rays from them are refracted by the earth’s atmosphere. Desert travelers sometimes see mirages which are caused by refraction through the atmosphere.
Bending Pencil: Refraction of Light Experiment. This is a very fast and easy experiment.
Materials you will need: Pencil, water, clear glass or a jar
Steps to follow:
* Fill the glass or jar half way with water.
* Place the pencil in the water.
* Look at the pencil from the top and then from the side.
Does the pencil look straight or bent? What happens when you look at the pencil through the side of the glass? Does light play tricks on your eyes?
The pencil looks bent. This is because light travels slower through water than through air. As the light enters the glass of water it slows down (changes direction) and as it leaves the glass it speeds up again – therefore making the pencil look as though it is bent.
Content for this question contributed by Annmarie Colucci, resident of Roselle, Union County, New Jersey, USA
