If i got my interval is 37 cm .And if i want to get in cm-1 I have to do this 1/37=0,027cm-1 right?
Yes, that's fine.
You want to get WHAT in cm-1? Not the same interval, I hope.
from some Lithium atomic spectrum which is equal 0.162A.This corresponds to 0.36cm-1
I still struggling to get this answer ,because if i take reciprocal of of it i can not get 0,36cm-1
0.162A is not even close to 1/3rd of cm. You are off by many orders of magnitude.
It would be a good start to figure out what are the quantities you are dealing with.
What quantity is given in A? Is it a wavelength?
And then what quantity do you want to calculate? Is it inverse wavelength or maybe the magnitude of the wave vector?
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