electromagnetic waves

• What type of spectrum do electromagnetic waves form?


  A continuous spectrum.
• What is the order of types 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 in a vacuum and in air.
• In which direction do waves refract when entering a denser medium?


  • They bend towards the normal
  • The angle of refraction is less than the angle of incidence
• Where do gamma rays originate from?


  They originate from changes in the nuclei of atoms.
• What health effects can ultraviolet waves cause?


  • They can cause the skin to age prematurely
  • They can increase the risk of developing skin cancer
• What health effects can X-rays and Gamma rays cause?


  • They are ionising radiation so can cause mutations in genes
  • They can lead to increased risk of developing various cancers
• 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