1. http://fc69.deviantart.com/fs36/f/2008/263/8/d/Explosion_of_Light_by_Bunniesandsheep.jpg Daniel Arnold Giovanni Cassarino William Hang Benjamin Hulbert Jerry Nguyen Matthew Robison Jared Sarabia

3. EM Waves in a Vacuum EM fields and waves can exist in a complete vacuum. EM waves are disturbances that vary in frequency. Without matter to disperse their energy, EM waves travel forever. They travel at the speed of light (c=186,000 miles/sec in a vacuum).

4. Electromagnetic Waves An EM wave is a disturbance in both a magnetic and an electric field. Most are invisible to us. Some can be felt as heat. Light is an EM wave. http://www.astronomynotes.com/light/emanim.gif

5. Radiation and Photons EM waves travel out from a source. Energy that moves in the form of EM waves is called radiation. EM radiation is produced by particles of energy called photons. A photon goes away when it is absorbed by matter.

6. Electromagnetic Spectrum The EM spectrum describes all frequencies of light. They are measured in Hertz: cycles per second. The ranges of EM waves include: – radio waves, microwaves, infrared light, visible light, ultraviolet light, x-rays, and gamma rays. http://science.hq.nasa.gov/kids/imagers/ems/waves.html

7. Radio Waves Radio waves are the lowest frequency. They can be produced by varying electric current in a wire. Radio waves can be used to send signals by varying the strength and/or the frequencies of the waves. Gamma X-ray Microwave Infrared Visible Radio Ultraviolet

8. Radio Waves http://upload.wikimedia.org/wikipedia/commons/7/72/Radio_transmition_diagram_en.pn g

9. Microwaves Radar bounces microwaves off of objects to determine their distance and speed. Microwave ovens use microwaves to heat and cook food. Gamma X-ray Microwave Infrared Visible Radio Ultraviolet http://upload.wikimedia.org/wikipedia/commons/4/43/C-band_Radar-dish_Antenna.jpg Cell phones use microwaves to send information to base stations.

10. Infrared Radiation Infrared waves are of slightly lower frequencies than visible light. They are given off by all matter. Night-vision goggles detect IR reflected by objects, allowing one to see in the dark. Gamma X-ray Microwave Infrared Visible Radio Ultraviolet http://www.i-globalmall.com/uploaded_images/Aevex_Glove_2_270x359-718150.jpg

11. Visible light occupies the narrowest range of the EM spectrum. The lowest frequencies are seen as red, and the highest are seen as violet. Gamma X-ray Microwave Infrared Visible Radio Ultraviolet Visible Light http://www.faqs.org/photo-dict/photofiles/list/699/1110prism.jpg

12. Gamma X-ray Microwave Infrared Visible Radio Ultraviolet UV light is invisible to humans. It can break apart molecules. It can damage cells if exposed to them for long periods of time. http://www.embedds.com/wp-content/uploads/2007i/0711/Ultraviolet_box_pcb.jpg Ultraviolet Light

13. X-rays X-rays are very high frequency and can pass through some matter. They can cause cancer. Microwave Infrared Visible Radio Ultraviolet http://www.spectrumdata.com.au/uploads/Xray_hand.jpg

14. Gamma Rays Gamma rays can pass through more objects than x-rays. They are produced by nuclear explosions and radioactive materials. They can cause severe damage to cells and are used to fight cancer. Microwave Infrared Visible Radio Ultraviolet http://jcconwell.files.wordpress.com/2009/07/supernova.jpg

16. Hot Matter Emits Light EM radiation is converted to light. Incandescent matter emits light. Light is produced by hot matter. Hotter matter emits more energy, and therefore light of higher frequencies. Light bulbs heat filaments to produce light. http://rakadd.files.wordpress.com/2009/10/11_12_52-electric-light-bulb_web.jpg

17. Chemical Reactions Emit Light Animals that give off light are bioluminescent. This light is cool. It is produced by a chemical reaction. http://b9hummingbirdhovering.files.wordpress.com/2009/05/firefly-glowwyrm.jpg

18. Charged Particles and Radiation Auroras are energized by fast-moving charged particles. When a gas emits light the light is a distinct color depending on the gas. Materials can get energy to produce radiation by first absorbing radiation. http://climatelab.org/@api/deki/files/191/=Compact_Fluorescent_Light_Bulb.jp g

19. Other Sources of Energy Some materials give off light when squeezed or broken. Semiconductors produce infrared light when a current is applied. The can also produce visible light as an light- emitting diode (LED). http://upload.wikimedia.org/wikipedia/commons/e/e9/Red_led_x5.jpg

21. How does light interact with matter? Light connects with matter in three basic ways: – transmitted, – reflected, and – absorbed.

22. Transmitted Light Matter can transmit light or let it pass by. Some materials such as air or clear glass for example glass windows allow light to come straight through. It can also be diffuse or spread out in many directions such as clouds or thin paper. http://livingindryden.org/images/home/finishedWindow06052005B.jpg

23. Reflected Light There are some materials, like books, that light can’t pass. So instead it reflects, or it bounces off of them. http://staffweb.wylieisd.net/staff/penciek/books3.gif

24. Adsorbed Light Light also can be absorbed by matter taking the energy of it. It is absorbed at the surface of a material. http://www.shortcourses.com/images/b4ch4/greenobject.jpg

25. Conclusion Most objects around us react to light in a different way. When light bounces off an object in the direction you’re in, your eye will detect it and you will see the object.

27. Color From Light Visible light is a mixture of different frequencies of light, which is detected by your eyes and produces light in side your brain. Depending on the properties of your eyes determines the color or shade that is produced.

28. Rod and Cone Cells Cone and Rod cells in your eye detect the brightness of light. Rod cells are long, thin cells that allow your eyes to see dim light such as moonlight. Cone cells are cone shaped cells that detect high levels of light and allow you to see color. http://www.uphs.upenn.edu/news/News_Releases/jun07/photoreceptor-diagram.jpg

29. Primary Colors of Light Originally light is split up into three colors, Red, Blue, and Green. When these colors mix they create the Pinks, Light Blues, Yellows and so on that we normally see. http://www.nitride.co.jp/english/images/tpcs.gif

30. Summary Light is an electromagnetic wave. – EM spectrum is divided by frequencies into 7 types. Light is produced in different ways. – Chemical, charged particles, radiation, etc. Light interacts with materials. – Absorption, transmission, reflection. Color comes from light. – Combinations of red, green, and blue.