William Herschel measured the temperature of different __________ of light. The temperature was lowest at the _______ end and highest at the ________ end. Curiosity led him to discover evidence of radiation ________ the band of ___________ light colors blue red past visible

The Waves of the Spectrum What waves are included in the electromagnetic spectrum? How is each type of electromagnetic wave used?

The Waves of the Spectrum The electromagnetic spectrum includes __________ waves, _____________ rays, ____________ light, _________________ rays, ____________, and _____________ rays. radio infrared visible ultraviolet X-rays gamma Electromagnetic Spectrum Song

The Waves of the Spectrum Visible light is the only part of the electromagnetic spectrum that you can ________, but it is just a small part. Each kind of wave is characterized by a range of _____________ and _________ _________. see frequencies wave- lengths

Radio Waves Radio waves are used in ____________ and _______________ technologies, as well as in ______________ ovens and __________. They have the ______________ wavelength and ____________ frequency of all the waves in the electromagnetic spectrum. radio television microwave radar longest lowest

Radio Waves The announcer’s voice and the music on CD leave the radio studio as electronic signals. Those signals are used to produce a wave with either a varying amplitude or a varying frequency. ______ waves have a varying amplitude. ______ waves have a varying frequency. AM FM Amplitude modulation Frequency modulation

Radio Waves Microwaves The shortest-wavelength radio waves are called ________________. Microwave wavelengths are from about 1 m to about 1 mm. Microwaves cook and ___________ food. Microwaves also carry ____________ conversations. The process works much like a radio broadcast. microwaves reheat cell phone

The word radar is an acronym for __dio ___etection and __anging. Radio Waves Radar The word radar is an acronym for __dio ___etection and __anging. The waves ___________ off the objects they encounter and bounce back toward where they came from. ra d r reflect

Infrared Rays Infrared rays are used as a source of ____________ and to discover areas of heat differences. Infrared rays have ____________ wavelengths than radio waves and ___________ frequencies. Warmer objects give off _________ infrared radiation than cooler objects. heat shorter greater more

A device called a thermograph Infrared Rays A device called a thermograph uses infrared sensors to create ________________, color-coded pictures that show variations in temperature. Search-and-rescue teams use infrared cameras to locate ____________ who are trapped during disasters. thermograms people

Infrared Rays A thermogram can be used to diagnose _____________ in a utility line. The colors in the thermogram image show that the electric current in the _____________ wire is not flowing as it should. problems middle

Visible Light People use visible light to __________, to help keep them ________, and to __________________ with one another. see safe communicate

Each color of light corresponds to a different range of _____________. Visible Light Each color of light corresponds to a different range of _____________. In order of decreasing wavelength, the colors spell out… wavelengths ROYGBIV

Ultraviolet Rays Ultraviolet rays have applications in ____________ and ________________, and in _____________________. These rays have ___________ wavelengths than visible light and ______________ frequencies. medicine health agriculture shorter higher

Ultraviolet Rays Some exposure to ultraviolet rays helps your skin produce vitamin ______, which helps the body absorb calcium from foods. Excessive exposure can cause sunburn, wrinkles, skin ____________, and eye damage. Ultraviolet rays are used to kill __________________. In winter, plant nurseries use ultraviolet lights to help plants __________. D cancer microorganisms grow

X-Rays X-rays are used in ____________, ____________, and transportation to make ___________ of the inside of solid objects. X-rays have very ________ wavelengths, ________ frequencies, and high _____________ that can penetrate matter that light cannot. Too much exposure to X-rays can _________ or damage living ____________. medicine industry pictures short high energy kill tissue

X-Rays Airport security screeners use X-rays to search baggage for potentially dangerous objects.

Gamma Rays Gamma rays are used in the medical field to __________ ________ cells and make pictures of the ___________, and in industrial situations as an inspection tool. kill cancer brain

Gamma Rays Gamma rays have the __________ wavelengths in the electromagnetic spectrum . They have the _____________ frequencies, the most energy, and the greatest penetrating ability of all the electromagnetic waves. Exposure to tiny amounts of gamma rays is _____________, but overexposure can be deadly. shortest highest tolerable

Gamma Rays Gamma rays emitted by radioactive tracers in the brain are used to produce color-coded images. Areas of high activity show up in red.

Which waves have the longest wavelength? Assessment Questions Which waves have the longest wavelength? radio waves infrared rays visible light ultraviolet rays

Assessment Questions What type of electromagnetic radiation is used to keep prepared foods warm in a serving area? ultraviolet rays infrared rays X-rays gamma rays

Assessment Questions 3. Visible light makes up a very large section of the electromagnetic spectrum. True or False False

4. What waves have the highest frequency and most energy? Assessment Questions 4. What waves have the highest frequency and most energy? ultraviolet rays infrared rays X-rays gamma rays