Question

what is the wave number of a radiation of wavelength 400mm?


​

Answer 1

Answer:

REFFER TO THE ATTACHMENT

Answer 2

Wavenumber of a wave is defined as  

ν

~

=  

λ

1

​

, where λ is the wavelength.

Given that wavelength of the photon is λ=400 nm=400×10  

−9

 m

Thus, wave number is  

ν

~

=(400)  

−1

 nm  

−1

=0.0025 nm  

−1