## Question

What is the transition in the hydrogen spectrum would have the same wavelength as the Balmer transition, *n* = 4 to *n* = 2 of He^{+} spectrum?

### Solution

*n* = 2 to *n* = 1

For H-like particle in general

∴ For He^{+} spectrum, for Balmer transition, *n* = 4 to *n* = 2.

For hydrogen spectrum

Which can be so for *n*_{1} = 1 and *n*_{2} = 2, i.e., the transition is from

*n* = 2 to *n* = 1.

#### SIMILAR QUESTIONS

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