Question

The wavelength of light of a particular wavelength received from a galaxy is measured on earth and is found to be 5% more that its wavelength. It follows that the galaxy is

Solution

Correct option is

Going away from the earth with a speed 1. 5 × 107 ms–1

 

If a source emitting light of wavelength λ goes away from the earth, the apparent wavelength λ’ of the light reaching the earth is given by   

                                

Where v is the speed of the source of light and c the speed of light. The increase in wavelength ∆λ = λ' – λ is given by

                              

           

SIMILAR QUESTIONS

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Q5

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Q6

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Q7

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Q8

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Q9

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Q10

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