Question

The wave number which corresponds to electromagnetic radiations of $600nm$ is equal to:

• A. $1.6\times {10}^4{cm}^{-1}$
• B. $0.16\times {10}^4{cm}^{-1}$
• C. $16\times {10}^4{cm}^{-1}$
• D. $160\times {10}^4{cm}^{-1}$

Answer 1

Answer: (A)

$1.6\times {10}^4{cm}^{-1}$

The wave number which corresponds to electromagnetic radiations of 600nm is $1.6\times {10}^4{cm}^{-1}$.
The wavelength $\lambda =600$ nm $=600nm\times {10}^{-7}cm=6\times {10}^{-5}cm$
The wavenumber $\overline{\nu }=\frac{1}{\lambda }$
$\overline{\nu }=\frac{1}{6\times {10}^{-5}cm}$
$\overline{\nu }=1.6\times {10}^4{cm}^{-1}$