6.2

• What type of spectrum do electromagnetic waves form?

  A continuous spectrum
• What is the order of electromagnetic radiation from lowest to highest frequency?

  • Radio waves
  • Microwaves
  • Infrared
  • Visible Light
  • Ultraviolet
  • X-rays
  • Gamma Rays
• How do the speeds of electromagnetic radiation differ in a vacuum and in air?

  They all travel at the same speed
• What property of waves in different mediums causes refraction?

  Velocity
• How does wave speed affect refraction in denser materials?

  Wave speed is slower in denser materials
• In which direction do waves refract when entering a denser medium?

  They bend towards the normal
• What type of waves can be produced by oscillations in an electrical circuit?

  Radio waves
• How can radio waves create an alternating current in a circuit?

  They induce oscillations at the same frequency
• Where do gamma rays originate from?

  Changes in the nuclei of atoms
• What health effects can ultraviolet waves cause?

  Skin aging and increased cancer risk
• What health effects can X-rays and gamma rays cause?

  They can cause mutations and increase cancer risk
• What are three practical uses for infrared radiation?

  1. Electrical heaters
  2. Cooking food
  3. Infrared cameras
• What are two practical uses for microwave radiation?

  1. Satellite communications
  2. Cooking food
• What are two practical uses for radio waves?

  1. Television transmission
  2. Radio transmission
• What colour of visible light has the highest frequency?

  Violet