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MAP:$25$ Electromagnetic Waves

The Electromagnetic Spectrum

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Introduction

Electromagnetic radiation is more common than you might expect. Radio and TV stations emit radio waves as they broadcast their programs; microwaves cook your food in a microwave oven; conventional ovens and stoves emit infrared and slightly visible radiation; dentists use X rays to check your teeth; and cell phones operate using microwaves as well, but at a lower frequency than microwave ovens. Even though they have different names and different applications, these types of radiation are really all the same thing: electromagnetic $($EM$)$ waves $$ energy that travels in the form of oscillating electric and magnetic fields. $$

Consider the following:

radio waves emitted by a weather radar system to detect raindrops and ice crystals in the atmosphere to study weather patterns;

microwaves used in communication satellite transmissions; $$

infrared waves that are perceived as heat when you turn on a burner on an electric stove;

the multicolor light in a rainbow;

the ultraviolet solar radiation that reaches the surface of the earth $$and causes unprotected skin to burn; and

X rays used in medicine for diagnostic imaging. $$

Part A

Which of the following statements correctly describe the various forms of EM radiation listed above?

Check all that apply.

View Available Hint$($s$)$for Part A

They have different wavelengths.They have different frequencies.They propagate at different speeds through a vacuum depending on their frequency.They propagate at different speeds through nonvacuum media depending on both their frequency and the material in which they travel.They require different media to propagate.

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Part B

Which of the following statements correctly describe the various applications listed above?

Check all that apply.

View Available Hint$($s$)$for Part B

None of these technologies use radio waves.None of these technologies use lower$-$frequency microwaves.None of these technologies use higher$-$frequency microwaves.None of these technologies use infrared waves.The radiation emitted by some wireless local area networks has the shortest wavelength of all the technologies listed above.All these technologies emit waves with a wavelength in the range $0\mathrm{.}01$ to $10\mathrm{.}0$ kmkm$.$All these technologies emit waves with a wavelength in the range $0\mathrm{.}01$ to $10\mathrm{.}0$ mm$.$