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Wave Optics — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsWave Optics2 Marks
Question
What does the red shift in the spectrum of a galaxy indicate?
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Answer

The red shift in the spectrum of the galaxy indicates that the apparent wavelength is increasing, according to the Doppler effect. This is because the galaxy is moving away from the Earth. That means the universe is expanding.

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