For a specific wavelength 670 nm of light coming from a galaxy moving with velocity v, the observed wavelength is 670.7 nm. The value of v is :
Solution
<p>$${\lambda _{obs}} = {\lambda _{source}}\sqrt {{{1 + {v \over C}} \over {1 - {v \over C}}}} $$</p>
<p>For $v < < C$,</p>
<p>${{670.7} \over {670}} = 1 + {v \over C}$</p>
<p>$\Rightarrow v = {{0.7} \over {670}} \times 3 \times {10^8}$ m/s</p>
<p>$\Rightarrow v \simeq 3.13 \times {10^5}$ m/s</p>
About this question
Subject: Physics · Chapter: Optics · Topic: Reflection and Mirrors
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