I am asked to construct a double-slit experiment for 5eV electrons. The first minimum of the diffraction pattern needs to occur at 5 degrees, what must the seperation of slits be?(adsbygoogle = window.adsbygoogle || []).push({});

I'm guessing that I should use Bragg's law but I dont know how to calcualte a minumum because bragg's law is for maximums.

[tex]\lambda=\frac{1240eVnm}{5eV}[/tex]

[tex]n \lambda=2dsin \theta[/tex]

[tex]1x240nm=2dsin5[/tex]

i would solve for d but wouldnt that be a maximum?

Also, I am asked to determin how far the slits have to be from the detector plan if the first minima on each side of the central maximum are seperated by 1 cm.

we know that theta is 5 and the height is 1 cm, so... using 1cm/theta(5)=11.4 cm? that doesnt seem right to me.

any ideas as to what i am doing wrong?

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# Homework Help: Bragg's law and double-slit experiment

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