1 / 19

Electromagetic Spectrum

EM Spectrum

meganhatton
Télécharger la présentation

Electromagetic Spectrum

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 22 Section 2 The Electromagnetic Spectrum

  2. Electromagnetic Spectrum • The entire range of EM waves • divided into regions according to the length of the waves

  3. Radio Waves • have some of the longest wavelengths and the lowest frequencies of all EM waves • wavelengths longer than 30 cm

  4. Radio Waves • used for broadcasting radio and TV signals • Changing amplitude or frequency of a wave is called modulation • AM -“amplitude modulation” • FM -“frequency modulation” • AM waves have longer wavelengths than FM waves • FM waves are less affected by electrical noise

  5. Why is FM used more often than AM?

  6. Microwaves • shorter wavelengths and higher frequencies than radio waves • wavelengths between 1 mm and 30 cm

  7. Microwaves • used to send information over long distances • Cellular phones, Satellites, radar • Radar (radio detection and ranging) is used to detect the speed and location of objects

  8. Infrared Waves • shorter wavelengths and higher frequencies than microwaves • wavelengths vary between 700 nanometers (nm) and 1 mm

  9. Infrared Waves • Almost everything give off infrared waves • The amount of infrared waves an object emits depends on the object’s temperature • Warmer objects give off more infrared waves than cooler objects

  10. Visible Light • wavelengths between 400 nm and 700 nm • Visible to the human eye • The visible light from the sun is white light • White light is visible light of all wavelengths combined

  11. Colors of Light ROY G. BiV

  12. Why can we see rainbows after a rainstorm?

  13. Ultraviolet Light • shorter wavelengths and higher frequencies than visible light • wavelengths vary between 60 nm and 400 nm • produced by the sun

  14. UV Effects Good Bad can cause: sunburn skin cancer wrinkles damage the eyes • UV lamps are used to kill bacteria on: • food • surgical tools • Small amounts are beneficial to your body by causing skin cells to produce vitamin D

  15. X Rays • wavelengths between 0.001 nm and 60 nm. • can pass through many materials, making them useful in the medical field • too much exposure to X rays can damage or kill living cells

  16. Why can to much x ray exposure be harmful?

  17. Gamma Rays • wavelengths shorter than 0.1 nm • penetrate most materials easily • treat some forms of cancer • used to kill harmful bacteria in meat and fresh fruits

More Related