Q: What speed should a galaxy move with respect to us so that the sodium line at 589.0 nm is observed at 589.6 nm ?
Sol: $\large \frac{\Delta \lambda}{\lambda} = \frac{v}{c} $
$\large v = \frac{0.6}{589} \times 3 \times 10^8 $
= 3.06 x 105 m/s
Science and Education
Q: What speed should a galaxy move with respect to us so that the sodium line at 589.0 nm is observed at 589.6 nm ?
Sol: $\large \frac{\Delta \lambda}{\lambda} = \frac{v}{c} $
$\large v = \frac{0.6}{589} \times 3 \times 10^8 $
= 3.06 x 105 m/s