Electromagnetic waves

• What is the electromagnetic spectrum?


  It is the entire range of electromagnetic waves.
• What are electromagnetic waves classified as?


  They are all transverse waves.
• How do electromagnetic waves oscillate?


  They oscillate perpendicular to the direction of energy transfer.
• What is the speed of electromagnetic waves in a vacuum?


  The speed is $3 \times 10^8 \text{ m/s}$.
• How do electromagnetic waves behave in different mediums?


  They travel at different speeds, which can lead to refraction.
• How many basic types of electromagnetic waves are there?


  There are seven basic types.
• What differentiates the types of electromagnetic waves?


  Their wavelength and frequency.
• What is the relationship between wavelength and frequency?


  They are inversely related.
• If the frequency of a wave increases, what happens to its wavelength?


  The wavelength decreases.
• Which type of electromagnetic wave has the largest wavelength?


  Radio waves.
• Which type of electromagnetic wave has the smallest wavelength?


  Gamma rays.
• What is the range of wavelengths for radio waves?


  They vary from multiple kilometers.
• What is the range of wavelengths for gamma rays?


  They are less than a thousandth of a nanometer.
• What part of the electromagnetic spectrum can human eyes detect?


  Visible light.
• What gives us the different colors we can see in visible light?

  The different wavelengths within this region.
• How can you memorize the order of electromagnetic waves in the spectrum?


  • Start with visible light in the middle.
  • Use the acronym "ROY G BIV" for colors:
  • Red, Orange, Yellow, Green, Blue, Indigo, Violet.
  • Ultraviolet follows violet, and infrared precedes red.
• What types of electromagnetic waves can be ionizing and cause damage to cells?


  Ultraviolet, X-rays, and gamma rays.
• What are the uses of microwaves and radio waves?


  They are used in communication.
• Where do electromagnetic waves come from?


  They come from everywhere.
• What can cause gamma rays to be emitted?


  Radioactive decay.
• What can cause visible light, ultraviolet, and X-rays to be emitted?

  When electrons drop down energy levels.
• What generates infrared radiation?


  Vibrations of the bonds that hold molecules together.
• What happens to electromagnetic waves when they come into contact with something?


  • They can be:
  • Reflected
  • Absorbed
  • Transmitted
  • Sometimes a combination of these three occurs.