August 13, 2007

Virtual Images

Today as I was driving down Ngauranga Gorge I saw a Rainbow. A full rainbow that stretched from left to right and was beautifully bright and colourful especially in contrast to the grey sky, concrete and asphalt. The traffic was going at a steady clip and this was enough to make me feel good about the day.

Rainbows are virtual images as opposed to real images and I'm not sure that I understand the difference but the simplest way for me to understand it is that real images can be projected onto something eg the image that a projector produces is a real image. You can put your hand in it and the image will be projected onto it. Virtual images cannot be touched. The image in a mirror or that of a rainbow is like that, you can see it but you can't ever reach it.

Physics is a bit like magic for me in that I don't understand how it works but it does work and makes awesome things happen.

Rainbows move and change because they are simply an image produced by light rays (often from the sun) reflecting and refracting off water droplets in the air and then those light rays hit the back of your eyes and you see the spectrum of light that is the rainbow. So, as you and the light and the water move so does the rainbow. Without one of those factors the rainbow will not appear. Without something to see them, rainbows do not exist.


Point of Fashion: Haircut!
Current Obession: Avoiding work

Posted by giffy at August 13, 2007 10:46 AM