what it is, how it works...
Different colors of light have there own wavelength. For example, voilet has a shorter wavelength than red.
The First Light Bulb
The first electric light bulb was made in 1800, by Humphry Davy.
The Speed of Light
The speed of light is 300,000 kilometers per second. (671 million miles per hour) which means that nothing travels faster than light. Light usually travels in a straight line and travels quicker than sound. It doesn't usually go around things. The speed of light in a vacuum is 300 million meters per second. The fastest thing in the universe is light. Nasa discovered that the words “faster than light” is called “Plausible.”
The Light in a Lighthouse
Convex lenses can magnify light. For example,There can be a small light bulb in a lighthouse, but the convex lenses that the light passes through make the light seen from far away.
Energy Efficient Light Bulbs
Energy efficient light bulbs can save energy. Compact fluorescent bulbs have 90% less energy than incandescent bulbs. Converting to CFL (compact fluorescent light) lights can save lots of money, and they produce almost no heat at all. They also lower carbon dioxide emissions.
LED Light Bulbs
LED stands for "Light-Emitting Diode". Unlike other lights, LED lights point light in one direction. LEDs last 3-5 times longer than a standard light bulb.
Light can still travel in a straight line even when passing through glass or liquid. If light hits glass or liquid at an angle, the line will be bent. Any transparent material can bend light and you can change the light distance of a bulb by using a convex lens. A convex lens is a lens that brings a beam of light to a point or focus because of its curved edge.
Light Visible to Animals
Animals can see part of the spectrum that humans can’t when the sun or other light shines on them.