Spectrum of singly ionised helium

[gianeshwar]

Dear Friends!
We know ionized helium has two protons in its nucleus, whereas hydrogen has one. This changes the line spectrum completely.
Why? Thank You in advance!

 

[mfb]

The attraction of the electron doubles at the same distance.
The line spectrum is not completely different, all energies are multiplied by a factor of 4.

 

[gianeshwar]

Thank You!
Frequency corresponding to first line in Laymen series in hydrogen spectrum is to be compared to the corresponding line in single ionised helium.
How to proceed to find the solution if relevant.
I am studying this subject after a long time ,but am keen.
I hope to accelerate my understanding with your expert guidance!
Thanks!

 

[mfb]

Just use the Rydberg formula. You'll see a factor of Z² there. It is 1 for hydrogen and 2²=4 for helium, everything else stays the same.