Primary Colours of Light red, green and blue are the primary colours when they combine they form other “secondary” colours

Colour white light is made up of all the other colours we can use a prism to split a ray of white light up into bands of different colours

The Spectrum when white light is refracted into different colours the resulting pattern is called a spectrum ROY G. BIV Red Orange Yellow Green Blue Indigo Violet

What is a rainbow? water droplets in the air act like a bunch of prisms… when sun shines on them they refract the light… and form a spectrum

Why do we see a certain color? white light (with all colors) strikes an object if all colors are reflected we see WHITE if no colors are reflected we see BLACK if one color is reflected … we see that color blue sky: particles of gas in the air are reflecting blue light green grass: grass is reflecting green

How do we see color? in the retina we have 2 kinds of cells that respond to light rods detect the presence of light (and dark) cones detect colour there are 3 types… one for each primary colour info from rods and cones go to the brain via the optic nerve your brain interprets the colours from the messages it gets

Color Blindness sometimes cone cells in people’s eyes are unable to detect certain colors this is an inherited trait called color blindness total color blindness: person does not see color partial color blindness people can’t distinguish between red & green people can’t distinguish between blue & yellow affects 8 – 12% males, less than 1% females most common