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ELECTROMAGNETIC WAVES — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsELECTROMAGNETIC WAVES2 Marks
Question
Write a short note on visible rays.
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Answer

→Visible rays are the part of the EM spectrum which is detected by human eye.
→Frequency range: 4 $\times$ $10^{14}$ Hz to about 7 $\times$ $10^{14}$Hz.
→Wavelength range: About 700-400 nm (or 7000 A° to 4000 A°).
→The visible light emitted or reflected from objects around us provide us information about the world.
→Different animals are sensitive to different range of wave lengths. For example, Snakes can detect infrared waves, and the 'visible' range of many insects extends well into the ultra violet.

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