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I have worked on this problem for about an hour, looked through the book lots of times, and honestly just don't know how to get it done. So I am here with all you fellow physicists for help! :)

X rays bombarding heavy atoms can be used

to eject electrons from the 1s shell in atoms;

indeed, this is the starting point for Moseley’s

experiments.

tons required to eject an electron from the 1s

shell of copper, for which Z = 29. Planck’s

constant is 6.63 × 10−34 J · s and the speed of

light is 3 × 108 m/s2. Answer in units of nm.

here is what I have found:

E=hc/lambda

lambdamin=hc/Ko

E=-(z)^2x13.6eV/n^2

These may seem like random equations, but honestly, these are all the ones I think that may be relevant. I can't figure out a starting point here at all.

I tried solving several times. I assume that since we are ejecting the electron from the 1S shell, it has very high energy since it's so close to the nucleus. I tried this

-z^2x13.6eV/n^2=hc/lambda to solve for lambda, but I am stuck with what to do with the quantum number. Does ejecting the electron from 1s change the n from 1 to something else?

Thanks

## Homework Statement

X rays bombarding heavy atoms can be used

to eject electrons from the 1s shell in atoms;

indeed, this is the starting point for Moseley’s

experiments.

**Estimate**the maximum wavelength of pho-tons required to eject an electron from the 1s

shell of copper, for which Z = 29. Planck’s

constant is 6.63 × 10−34 J · s and the speed of

light is 3 × 108 m/s2. Answer in units of nm.

## Homework Equations

here is what I have found:

E=hc/lambda

lambdamin=hc/Ko

E=-(z)^2x13.6eV/n^2

These may seem like random equations, but honestly, these are all the ones I think that may be relevant. I can't figure out a starting point here at all.

## The Attempt at a Solution

I tried solving several times. I assume that since we are ejecting the electron from the 1S shell, it has very high energy since it's so close to the nucleus. I tried this

-z^2x13.6eV/n^2=hc/lambda to solve for lambda, but I am stuck with what to do with the quantum number. Does ejecting the electron from 1s change the n from 1 to something else?

Thanks

**Edit: What's weird is that the question also asks to "estimate" the max wavelength. Does that in any way change anything?**
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