If you want to look at the questions now, you canĀ click here.
Our eyes can see many of these waves, but not all! For example, the shortest waves that we can see are purple light. The purple color with the shortest wave is violet. Waves that are a little bit shorter create āultra-violetā waves. These waves are too close together for our eyes to see. The Sun creates radiant energy, which includes ultra-violet waves, and many other invisible waves. Have you ever been sunburned? You can blame the ultra-violet light waves!
Waves shorter than ultra-violet waves can fit into small places. That is why they are used for X-rays. They are also created by nuclear power plants. Nuclear power plants use reactions between the smallest particles of matter to create a HUGE amount of energy. Because these particles are so small, their electromagnetic waves are even smaller than X-rays.
Red is the visible light wave with the longest waves. Waves that are a little bit longer are called infrared waves. Your remote control uses infrared waves to communicate with your TV. Scientists found that heat sources send out infrared waves, too. Guess what? You are a heat source, and you send out infrared waves! By measuring infrared waves, we can know how hot something is.
Waves longer than infrared waves are useful for running cell phones, radios, and satellites.
Waves shorter than ultra-violet waves are useful for investigating small things. Each wavelength has its own special uses!
But, how fast are these waves?
You know that the speed of light is super fast. Itās actually 670,616,629 miles per hour! All electromagnetic waves travel at the same speed. Remember, light is an electromagnetic wave. All electromagnetic waves travel at the speed of light! So, a radio tower and an X-ray machine create waves that travel at 670,616,629 miles per hour!