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fatherdaly
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Homework Statement
A thin polycrystalline film of Cu, with lattice parameter of 0.361 nm, is irradiated with X-rays with wavelength of 0.154 nm. Calculate the first 5 bragg scattering angles for which X-rays may be detected.
Homework Equations
2dsin([tex]\theta[/tex]) = n[tex]\lambda[/tex]
Bragg condition for constructive interference.
n is an integer.
The Attempt at a Solution
That seems the obvious equation to be using here. I rearrange it for theta
[tex]\theta[/tex] = arcsin(n[tex]\lambda[/tex]/2d)
Like that. Then I put in the numbers for n = 1, 2, 3 etc
For n=1 I get, 12.3 ish degrees
For n=2, 25.3 degrees
n=3, 39.8 degrees
n=4, 58.6
n=5, well you can't arcsin something that's >1.
Therein lies the problem. Also I have access to the answers and they're not the same as mine. I can provide them if anyone wants to know.
Please help. Not even google is able to provide answers.