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The 6563Å Halpha line emitted by hydroge...

The `6563Å Halpha` line emitted by hydrogen in a star is found to be redshifted by `15Å`. Estimate the speed with which the star is receding from the Earth.

A

`686xx10^(5)ms^(-1)`

B

`-686xx10^(5)ms^(-1)`

C

`6.86xx10^(5)ms^(-1)`

D

`-6.86xx10^(5)ms^(-1)`

Text Solution

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The correct Answer is:
D
For answer see Physics Darpan, Part-2, Section-B, Exercises of Textbook example no. 10.11
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