Making Waves

Try Answering This

  1. Ultraviolet light penetrates our skin and gets stopped (absorbed) by the tissues just beneath it. X-rays penetrate all the way through skin and muscle and are finally stopped by bones and denser objects. Why does X-ray light get farther into our bodies than ultraviolet?
    Answer: The amount of energy carried by an electromagnetic wave depends on its frequency: the higher the frequency, the more energetic the wave. X-ray light has a higher frequency than ultraviolet light so it has more energy and can travel farther through denser material than ultraviolet light before being stopped.

  2. When you tune your radio (it receives radio light!) to a particular station, the dial shows the frequency at which the station broadcasts. For example, to listen to WROC you turn the dial to 101 Megahertz (101 million cycles per second). Instead of displaying the frequency, could the dial on the radio just as well show wavelength? Why?
    Answer: The use of frequency units (cycles per second) to describe radio waves is just a matter of tradition. Wavelengths could be displayed on your radio dial and would work just as well. (As long as the radio stations identify their wavelength setting! Otherwise, you'd have to do the conversion yourself to know what wavelength to tune to!)

  3. What if we lived on Venus instead of Earth? The dense clouds forever blanketing that planet would block all starlight. Would we ever know that there are such things as stars?
    Answer: Even though we would not be able to see stars in the visible spectrum, it still could be possible to detect their presence by using another wavelength in of the electromagnetic spectrum. Since radio waves, for example, would penetrate the Venusian atmosphere without trouble, we could detect things in the sky that give off energy in radio wavelengths.

  4. Why is the order of colors in a rainbow always the same? For example, why is red never right next to blue??
    Answer: Colors in a rainbow will always appear in the same order because light waves arrange themselves by their wavelength and frequency. Since violet waves are just a little shorter than blue and blue waves are just a little shorter than green, blue will always be between violet and green. Each color’s wavelength is just a little shorter than the previous one so green is next to yellow, yellow is next to orange and orange is next to red.