2. Electromagnetic communication21 Mar Class listSeating Plan Electromagnetic communication 21 Mar 2012

3. Electromagnetic communication21 Mar Class listSeating Plan Learning Objectives Be able to describe: how radio waves, microwaves and infra-red radiations can be used for communication. – Level 5-7 Be able to describe why different radiation is used for different communication. – Level 3-5

4. Electromagnetic communication21 Mar Class listSeating Plan Light tech Compile a list of different gadgets and gizmo’s that use the following Electromagnetic radiation. (try to link the radiation to the gizmo if you can) – Visible lightInfra redMicrowave – RadioUltraviolet

5. Electromagnetic communication21 Mar Class listSeating Plan Light waves have an electric component

6. Electromagnetic communication21 Mar Class listSeating Plan Electromagnetic waves need a medium to travel through

7. Electromagnetic communication21 Mar Class listSeating Plan When an electromagnetic wave passes over a conductor something happens

8. Electromagnetic communication21 Mar Class listSeating Plan In space noone can hear you scream

9. Electromagnetic communication21 Mar Class listSeating Plan

10. Electromagnetic communication21 Mar Class listSeating Plan Radio

11. Electromagnetic communication21 Mar Class listSeating Plan Radio

12. Electromagnetic communication21 Mar Class listSeating Plan Radio

13. Electromagnetic communication21 Mar Class listSeating Plan Radio Our first means of wireless communication, invented by a local. Marconi. Very long wavelength (km) Very low frequency (kHz) Can pass through a lot of materials (people, walls etc.) Can bounce off the atmosphere – Can be good – Can be bad

14. Electromagnetic communication21 Mar Class listSeating Plan Radio

15. Electromagnetic communication21 Mar Class listSeating Plan Microwaves Used in Satellites – they pass through the atmosphere more easily. Much smaller wavelength (cm) Much higher frequency (MHz – GHz) Microwaves are absorbed by metals much like radio waves.

16. Electromagnetic communication21 Mar Class listSeating Plan Infra-red and Visible

17. Electromagnetic communication21 Mar Class listSeating Plan Infra-red and visible Used in Fibre optics: Law of refraction – Total internal reflection

18. Electromagnetic communication21 Mar Class listSeating Plan

19. Electromagnetic communication21 Mar Class listSeating Plan Radio

20. Electromagnetic communication21 Mar Class listSeating Plan 6 mark question Explain using what you know about Electromagnetic radiation, which type of radiation is used for TV, Satellite and Endoscopes and why. For full marks you need to explore the relationship between wavelength of EM radiation and transparency of media.