Q. The wavelength of yellow line of sodium is $5896\mathring{\mathrm{A}}$. Its wave number will be
A) $50883 \times 10^{10}$ per second
B) 16961 per $cm$
C) 17581 per $cm$
D) 50883 per $cm$
Explanation
(b) Wave number $\overline{v} = \frac{1}{\lambda} = \frac{1}{5896 \times 10^{- 8}} = 16961$ per $cm$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.