Conquer It

Read the following excerpt from the article and then complete the activity below. As you read, examine the details to determine the central idea.

LED bulbs are much brighter, last much longer and use much less energy than old-fashioned incandescent lightbulbs. Incandescent bulbs use electricity to heat a thin metal strand called a filament. It wastes energy by giving off both heat and light. Instead, LEDs change energy into light, without the heat.

LEDs also avoid problems of fluorescent lights. They are the long, thin bulbs that light office ceilings. They rely on mercury, which pollutes the environment when it is thrown away.

LED technology now lights our smart phone screens and phone flashlights, as well as many household lights. Even the twinkling lights put on Christmas trees are LEDs. And because ultraviolet light kills bacteria, blue LEDs could potentially be used to purify drinking water in the future, Delsing said.

The prize is "to be given for inventions that benefited mankind.”

Newsela Opens a new window, October 8, 2014