Choosing the Right Color: 1  Light color is measured on a temperature scale referred to as Kelvin (K). 2  Lower Kelvin numbers mean the light appears more yellow; higher Kelvin numbers mean the light is whiter or bluer. 3  Most ENERGY STAR certified bulbs are made to match the color of incandescent bulbs at 2200-3000K. For a whiter light, look for bulbs marked 3500-4100K. For bluer white light, look for bulbs marked 5000-6500K.
Visible Light. Visible Light Waves Visible light waves are the only electromagnetic waves we can see. We see these waves as the colors of the rainbow. Each color has a different wavelength. Red has the longest wavelength and violet has the shortest wavelength. When all the waves are seen together, they make white light.
(Answer #1). A rainbow is composed of the entire spectrum of colors of visible light, from the longest wavelength, red, to the shortest wavelength, violet. The order of colors in a rainbow is easiest to remember by the following mnemonic (a formula that helps one remember something): ROY G. BIV.