electromagnetic waves

• What type of waves are electromagnetic waves?

  Transverse waves
• What do electromagnetic waves transfer from the source to an absorber?

  Energy
• What are the shared properties of all electromagnetic waves?

  • They are all transverse
  • They can travel through a vacuum
  • They all travel at the same speed in a vacuum
• How many types of electromagnetic waves are there?

  Seven types
• What is the relationship between wavelength and energy in electromagnetic waves?

  Shorter wavelength means higher energy
• Which types of EM waves carry higher energy?

  UV, X-rays, and gamma rays
• What happens to the danger level of EM waves as their energy increases?

  The danger level increases
• How do microwaves transfer energy?

  • Water molecules absorb certain wavelengths
  • Microwave ovens heat food by transferring energy
• How do hot objects emit energy?

  • All hot objects emit infrared radiation
  • Absorbed by other objects, warming them
• What types of EM radiation does the Sun emit?

  Visible light, infrared, and ultraviolet
• What are the main groupings of the electromagnetic spectrum?

  1. Radio waves
  2. Microwaves
  3. Infrared
  4. Visible light
  5. Ultraviolet
  6. X-rays
  7. Gamma rays
• What mnemonic can help remember the EM spectrum order?

  Raging Martians Invaded Venus Using X-ray Guns
• What is the visible light spectrum's percentage of the whole EM spectrum?

  0.0035%
• How do animals perceive light differently than humans?

  Some see infrared and UV wavelengths
• What is the relationship between wavelength and frequency in the EM spectrum?

  • Wavelength and frequency are inversely proportional
  • Increase in wavelength = decrease in frequency
  • Decrease in wavelength = increase in frequency
• What happens to EM waves when they enter a different medium?

  They may undergo refraction
• What causes the refraction of EM waves?

  Difference in velocity in different substances
• What is dispersion in the context of EM waves?

  Different wavelengths slow down by different amounts
• Which color of light is refracted the most?

  Violet light
• What are the possible interactions of EM waves with matter?

  • Transmitted
  • Absorbed
  • Reflected
  • Refracted
• What determines how EM waves interact with different materials?

  The wavelength of the waves and the material
• What happens to the energy of EM waves as frequency increases?

  The energy increases
• What is the effect of ionising radiation on human tissue?

  It can damage cells and cause mutations
• Which EM waves are considered highly ionising?

  Ultraviolet, X-rays, and gamma rays
• What are the dangers associated with microwaves?

  Risk of internal heating in humans
• How do good quality sunglasses protect eyes?

  They absorb ultraviolet light
• What precautions do medical professionals take with X-rays?

  Leave the room during X-ray exposure
• What are the applications of electromagnetic waves?

  • Communication
  • Medical imaging
  • Heating food
  • Observing celestial bodies
• How do atoms interact with electromagnetic waves?

  They can absorb or emit EM waves
• What happens when an EM wave hits an atom's electron?

  The electron gains energy and moves up
• What produces radio waves?

  High-frequency alternating current in an antenna
• How do radio waves induce currents in receiving aerials?

  By absorbing radio waves with the same frequency