JEE Mains · Physics · STD 12 - 10. Wave optics
With what speed should a galaxy move outward with respect to earth so that the sodium-D line at wavelength \(5890\) \(\stackrel{\circ}{{A}}\) is observed at \(5896\) \(\stackrel{\circ}{{A}}\) ? (in \({km} / {sec}\))
- A \(336\)
- B \(296\)
- C \(306\)
- D \(322\)
Answer & Solution
Correct Answer
(C) \(306\)
Step-by-step Solution
Detailed explanation
\(\frac{\Delta \lambda }{\lambda }=\frac{v}{c}\) \(v=6 \times \frac{3\times 10^8}{5890}=305.06\, {km} / {s}\)
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