Okay, we have a graph that shows how v.high energy electrons are diffracted by atomic nuclei and the first minimum is shown to be at approximately 51 degrees for carbon-12 with energy 420MeV. To calculate the nuclear radii I decided to use sin(theta)= 1.22lambda/d and rearranged this so d was the subject of the eq. To work out lamba I used lamba= h/sqrt(2mE). Then to finally calculate the radius of this nucelus, I used R=d/2. However, I've ended up with an answer x10^-14 (and almost x10^-13).(adsbygoogle = window.adsbygoogle || []).push({});

Can someone please tell me what's wrong with this? I've used m as the mass of an electron and put the energy into joules so I've got 420x10^6x1.6x10^-19 J

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# Simple Measurement of Atomic Nuclei Radii

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