Electromagnetic Waves

• What is meant by the electromagnetic spectrum?

  It refers to the range of all types of electromagnetic radiation.
• What are the different waves in the electromagnetic spectrum in order of wavelength and frequency?

  • Radio waves
  • Microwaves
  • Infrared
  • Visible light
  • Ultraviolet light
  • X-rays
  • Gamma rays
• How do electromagnetic waves transfer energy?

  They transfer energy from the source to an absorber.
• What happens when white light passes through a prism?

  It splits into a spectrum of colors.
• What part of the electromagnetic spectrum can be detected by the human eye?

  Visible light is the only part that can be detected by the human eye.
• What is the relationship between wavelength and frequency in the electromagnetic spectrum?

  • Waves on the red end have lower frequency and longer wavelength.
  • Waves on the violet end have higher frequency and shorter wavelength.
• What phrase can help remember the order of the electromagnetic spectrum?

  Raw meat is very unsanitary except giraffe.
• How does the frequency and wavelength change across the electromagnetic spectrum?

  Frequency increases and wavelength decreases from radio waves to gamma rays.
• Do electromagnetic waves need a medium to travel?

  No, they can travel through a vacuum.
• What is the speed of electromagnetic waves in a vacuum?

  300 million meters per second or $3 \times 10^8 \text{ m/s}.$
• How do different materials interact with electromagnetic waves?

  • Absorb
  • Transmit
  • Reflect
• What determines how electromagnetic waves behave when they encounter materials?

  It depends on the wavelength of the waves.
• How are microwaves absorbed by food?

  They are absorbed by foods containing water molecules.
• How do microwaves interact with metals?

  They are reflected from metals.
• How do light waves interact with black surfaces and shiny metallic surfaces?

  Light waves are absorbed by black surfaces and reflected from shiny surfaces.