Question
Due to Doppler effect, the shift in wavelength observed is $0.1\;\mathring A $, for a star producing a wavelength $6000\;\mathring A $. The velocity of recession of the star will be ....... $km/sec$
✓
Answer
c
$\frac{\Delta \lambda}{\lambda}=\frac{v}{c}$
$\frac{\Delta \lambda}{\lambda}=\frac{v}{c}$
$\frac{0.1}{6000}=\frac{v}{3 \times 10^{8}}$
$v=5\; km / s$
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