MAP TAP The Electromagnetic Spectrum1 Wavelength/frequency/energy

MAP TAP The Electromagnetic Spectrum2 What is it? The electromagnetic spectrum is the complete spectrum or continuum of light including radio waves, infrared, visible light, ultraviolet light, X- rays and gamma rays An electromagnetic wave consists of electric and magnetic fields which vibrates thus making waves.

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MAP TAP The Electromagnetic Spectrum5 Wavelength, Frequency and Energy Since all light travels at the same speed, wavelength and frequency have an indirect relationship. Light with a short wavelength will have a high frequency and light with a long wavelength will have a low frequency. Light with short wavelengths has high energy and long wavelength has low energy

MAP TAP The Electromagnetic Spectrum6 Waves Properties of waves include speed, frequency wavelength, and energy. Speed (v), frequency (f) and wavelength ( ) are related in the formula v= f x All light travels at a speed of 3 X 10 8 m/s in a vacuum (c= speed of light) Energy is related to frequency E = ħf

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MAP TAP The Electromagnetic Spectrum8 Radio waves Low energy waves with long wavelengths Includes FM, AM, radar and TV waves Wavelengths of m and longer Low frequency Used in many devices such as remote control items, cell phones, wireless devices, etc.

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MAP TAP The Electromagnetic Spectrum10 Microwaves Shorter than radio, longer than light and infrared Wavelength 1 x m to 1 x m First used in radar, now used in communication, medicine, and consumer use (microwave ovens)

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MAP TAP The Electromagnetic Spectrum12 Infrared waves Invisible electromagnetic waves that are detected as heat Can be detected with special devices such as night goggles Used in heat lamps, ac/heating industry Higher energy than microwaves but lower than visible light Can be used to detect poor insulation in houses.

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MAP TAP The Electromagnetic Spectrum14 Visible Light The portion of the electromagnetic spectrum that human eyes can detect ROY G BIV (red, orange, yellow, green, blue, indigo, violet) Red is the lowest frequency and violet is the highest frequency Usually reported in nanometers (10 -9 m)

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MAP TAP The Electromagnetic Spectrum16 Ultraviolet waves Higher energy than light waves Can cause skin cancer and blindness in humans Used in tanning beds and sterilizing equipment

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MAP TAP The Electromagnetic Spectrum18 X-Rays High energy waves! Used in medicine, industry and astronomy Can cause cancer if you get more than a few dozen per year, depending on where youre getting the imaging on your body. That was my thumb last spring break….

MAP TAP The Electromagnetic Spectrum19 Gamma rays Highest energy, generated by nuclear explosions in stars Blocked from Earths surface by atmosphere Used in cancer therapy since they kill cells Gamma-ray bursts from outside our galaxy can release more energy in 10 seconds than the Sun will emit in its entire 10 billion-year lifetime!

MAP TAP The Electromagnetic Spectrum20 Time to think….. 1. What is the relationship between frequency and wavelength? 2. What is meant by spectrum? 3. What does ROY G BIV mean?

MAP TAP The Electromagnetic Spectrum21 Now, lets really think 4. Can you actually see x-rays? –Support your answer. 5. Which color is more energetic, red or yellow? 6. Which type of wave travels faster, gamma or radio? 7. Why are microwaves more dangerous than radio waves?

MAP TAP The Electromagnetic Spectrum22 Think about it…. You have just been involved in a traffic incident that leaves you stranded on the side of the road. Which part of the electromagnetic spectrum would be of the most use to you and why?

MAP TAP The Electromagnetic Spectrum23 Answers 1. Frequency and wavelength are properties of waves and since speed is constant for EM waves, as frequency increases, wavelength decreases. 2. Spectrum is a continuum of all electromagnetic waves 3, ROY G BIV is the difference colors of the visible light in order of longest wavelength to shortest wavelength. 4. X-rays can not be seen, only the waves in the visible light portion are visible. 5. Yellow is higher energy than red because it has a shorter wavelength and higher frequency. 6. Both travel at the same speed, 300,000 km/s (all em waves travel at the same speed) 7. Microwaves have a higher frequency than radio and carry more energy.