Optics Question 249
Question: A star emitting radiation at a wavelength of $ 5000{AA} $ is approaching earth with a velocity of $ 1.5\times 10^{6}m/s $ . The change in wavelength of the radiation as received on the earth, is
[CBSE PMT 1995]
Options:
A) $ 25{AA} $
B) Zero
C) $ 100{AA} $
D) $ 2.5{AA} $
Show Answer
Answer:
Correct Answer: A
Solution:
$ \Delta \lambda =\lambda .\ \frac{v}{c}=\frac{1.5\times 10^{6}}{3\times 10^{8}}\times 5000=25{AA} $
