SIMPLE EXPERIMENT: LAW OF REFLECTION

This activity investigates the rule of reflection, which focuses on obtaining, collecting, and considering evidence. The students should learn and remember the basic terms that are associated with the law of reflection.

When you look in a mirror, you can see a reflection of yourself.  If you look at texts on the newspapers or magazines, they appear to be reversed, which is the way light is reflected by a mirror. How can we investigate this phenomenon? What is reflection? What is the law of reflection?

In this practical, you need plane mirrors, concave, and convex mirrors.  Your focus is on making measurements accurately, recording the results, and making conclusions from the evidence collected.

USEFUL INFRA-RED

The sun is a primary source of the Earth’s energy.  In fact, the energy to heat us up travels from it at the speed of light, just like the light rays.  This particular energy rays that cause the most heating are called infra-red rays.  These are also light rays but of longer wavelength. Since it is a light ray, it can also be reflected by mirrors. This is where the idea of ‘solar furnace’ comes about, particularly in hotter parts of the world where solar furnace is used, to collect the rays from the sun and focus them on to kettles or cooking pans.

Activity

On a sunny day, take a concave mirror outside to heat a spoonful of water.

OR

Take the same concave mirror outside to light a match. It would help better if you first blacken the head of the match with a pencil.

Note:

Be very careful in conducting this practical.