JEE Mains · Physics · STD 12 - 10. Wave optics
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 ............
- A \(3 \times 10^{8} \; ms ^{-1}\)
- B \(3 \times 10^{10} \; ms ^{-1}\)
- C \(3.13 \times 10^{5} \; ms ^{-1}\)
- D \(4.48 \times 10^{5} \; ms ^{-1}\)
Answer & Solution
Correct Answer
(C) \(3.13 \times 10^{5} \; ms ^{-1}\)
Step-by-step Solution
Detailed explanation
\(\lambda_{\text {emitted }}=670 \; nm\) \(\lambda_{\text {obs }}=670.7 \; nm\) \(v =?\) \(c =3 \times 10^{8} \; m / s\) If \(v << c\) \(\frac{\lambda_{\text {obs }}-\lambda_{\text {emitted }}}{\lambda_{\text {emiited }}}=\frac{ v }{ c }\)…
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