Today’s Wonder of the Day was inspired by steve. steve Wonders, “What is a LED lightbulb?” Thanks for WONDERing with us, steve!

Have you ever imagined what life was like before light bulbs? There were many parts of life that were more difficult. People used candles, torches, and lanterns to light their homes. Playing a family board game after dinner would require a gaslit lamp. You‘d even need to light a candle to read a bedtime story! It‘s no secret that the light bulb changed the world.

Thomas Edison invented the light bulb in 1879. Since then, people have made many improvements to lighting. Look around you. How many types of lights do you see? Your lamp table at home probably has a regular light bulb. It’s what scientists call an incandescent bulb. Fluorescent tubes might light your school. In some cases, lights contain LEDs.

LED stands for light-emitting diodes. American Nick Holonyak, Jr., made the first LED in 1962. Today, these bulbs are found in all sorts of things. Have you ever seen a digital clock? How about a remote control? Both of these devices use LEDs to make light and send signals. LEDs can light up wristwatches and traffic lights. Your television might also use LEDs!

But what exactly are LEDs? Basically, like tiny light bulbs that are part of a simple electrical circuit. They’re different from regular light bulbs in many ways. They don‘t get very hot, which makes them safer for homes with young kids. They also send light in one direction, which makes them useful for task lighting. These features make LEDs very popular for many products.

LEDs work by moving electrons across a semiconductor. This movement of the electrons causes the release of light. The shape of the LED bulb then directs the light outward.

Have you ever turned on a light switch just to find that the bulb has burned out? Regular light bulbs often burn out after a few hundred hours of use. LED bulbs can last 25,000 hours. That‘s over three years if they’re on 24 hours a day!

LEDs usually cost more to buy than regular light bulbs. However, they use power. People who use LEDs at home find that it lowers their electric bills. Since they also last much longer than regular bulbs, LEDs end up being cheaper in the long run.

In 2012, 49 million LEDs were installed in the US. Together, they saved about $675 million in energy costs. If the entire US switched to LEDs, it would save $250 billion over the next two decades! This would also lower carbon emissions by 1,800 million metric tons.

What other uses might people find for LEDs? Will an even better bulb come along? Only time can tell! What other alternatives to regular light bulbs can you think of?

Standards: CCRA.L.3, CCRA.L.6, CCRA.R.1, CCRA.R.2, CCRA.R.10, CCRA.L.1, CCRA.L.2, CCRA.SL.1, CCRA.W.2, CCRA.W.9

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