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प्रश्न
Explain red shift and blue shift in Doppler Effect.
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उत्तर
If the spectral lines of the star are found to shift towards red end of the spectrum (called redshift) then the star is receding away from the Earth. If the spectral lines of the star are found to shift towards the blue end of the spectrum (called blue shift) then the star is approaching Earth.
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- if the observer is in front of the source.
- if the observer is behind the train.
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