Optics Question 266
Question: Light from the constellation Virgo is observed to increase in wavelength by 0.4%. With respect to Earth the constellation is
[MP PET 2003]
Options:
A) Moving away with velocity 1.2 x 106 m/s
B) Coming closer with velocity 1.2 x 106 m/s
C) Moving away with velocity 4 x 106 m/s
D) Coming closer with velocity 4 x 106 m/s
Show Answer
Answer:
Correct Answer: A
Solution:
Using $ \frac{\Delta \lambda }{\lambda }=\frac{v}{c}\Rightarrow v=\frac{\Delta \lambda }{\lambda }c $
$ \Rightarrow v=0.004\times 3\times 10^{8}=1.2\times 10^{6} $ m/sec
