MCQ
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 ....... $km/sec$
- A$2.5$
- B$10$
- ✓$5 $
- D$20 $
✓
Answer
Correct option: C.
$5 $
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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