Optics Question 263
Question: A heavenly body is receding from earth such that the fractional change in l is 1, then its velocity is
[DCE 2000]
Options:
A) C
B) $ \frac{3C}{5} $
C) $ \frac{C}{5} $
D) $ \frac{2C}{5} $
Show Answer
Answer:
Correct Answer: A
Solution:
$ \frac{\Delta \lambda }{\lambda }=\frac{v}{c}\Rightarrow 1=\frac{v}{c}\Rightarrow v=c $