This is a fairly basic experiment in which we demonstrate how a mirror reflects light.
| Some space |
| A big mirror |
| Someone else |
| A lot of string |
Place the mirror up against the wall. Make sure it’s in the centre of the wall if possible. (Lengthways that is). Get you friend to stand somewhere in the room. Next lay a piece of string between your friend and the bottom centre of the mirror (make sure its as straight as you can get it). Now you go and stand somewhere else in the room where you can see your friend (as much of him as possible) in the mirror. Stand still and Get your friend to lay a piece of string between you and the mirror, like you did before. (you should end up as in the first picture)
When you compare the two lines drawn by the string, you should notice that wherever you and your friend stand, the angle between your string and the mirror and your friends string and the mirror is always the same. (Have a look a the second picture)
Mirrors always reflects light way at the same angle as they receive it. This is an important thing to learn so we’ll say it again in different way (and louder). The angle at which light hits a mirror is the same as the angle at which it reflects off. (See third picture)
You’ve probably noticed this for yourself but might not have thought it about as such. Think about the light coming from your friend for a moment. When it hits the mirror, it can only bounce back at the same angle at which it hit it. You’ll only be able to see your friend then, if you stand along the line where your angle to the mirror is the same as your fiends. Once on this line, however, you or your friend can move anywhere along it and will always be able to see each other
We’ve probably gone on too much about this now. So using your new-found knowledge you can try your hand at the mirror maze or making a periscope.