# plane mirror

• Dec 1st 2008, 05:36 PM
iamanoobatmath
plane mirror
Quote:

Draw a diagram illustrating that the minimum size of a plane mirror that shows you your whole body is half your height.
I don't understand. How does a plane mirror shrink your size? Isn't that for convex/concave?
• Dec 1st 2008, 05:43 PM
vincisonfire
It doesn't shrink you size.
The mirror is half your height, suppose the top is at the level of your hair. Then you will be able to see your feet. This is what the statement tells you.
• Dec 1st 2008, 07:32 PM
iamanoobatmath
http://img114.imageshack.us/img114/3443/shoopbj8.gif the blue dot is an eye
First law of reflection, angle of incidence= angle of reflection?
• Dec 1st 2008, 08:55 PM
Shyam
Quote:

Originally Posted by iamanoobatmath
I don't understand. How does a plane mirror shrink your size? Isn't that for convex/concave?

your question says that if the height of plane mirror is half of your height, then only you can see your full height in the mirror.
If your height is h, then, the height of plane mirror would be h/2.