Dual Nature Of Light Question 532
Question: The wavelength of $ {K_{\alpha }} $ line for an element of atomic number 43 is l. Then the wavelength of $ {K_{\alpha }} $ line for an element of atomic number 29 is
Options:
A) $ \frac{43}{29}\lambda $
B) $ \frac{42}{28}\lambda $
C) $ \frac{9}{4}\lambda $
D) $ \frac{4}{9}\lambda $
Show Answer
Answer:
Correct Answer: C
Solution:
$ \lambda ,\propto \frac{1}{{{(Z-1)}^{2}}} $
$ \Rightarrow \frac{{\lambda_{2}}}{{\lambda_{1}}}={{( \frac{Z_{1}-1}{Z_{2}-1} )}^{2}} $
$ \Rightarrow \frac{{\lambda_{2}}}{\lambda }={{( \frac{43-1}{29-1} )}^{2}}={{( \frac{42}{28} )}^{2}} $
Þ $ {\lambda_{2}}=\frac{9}{4}\lambda $ .
BETA
