How would you use electron diffraction to estimate nuclear diameter

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So electrons fall into the category of particles called lepton s with don't interact with the strong nuclear force, this means they can be used for diffraction without getting affected too much by the nuclei they are intended to measure. This is because neautrons and alpha particles are affected by the strong nuclear force. 

A beam of moving electrons ahs a de Broglie wavelength which at high speeds is approximated by hc/E where h is the planck constant, c is the speed of light and E is the charge in coulombs. Remember that in a question you're likely to get the beam strength in MeV so you need to times by 1.6*10-19 to get to coulombs!

Once we have the wavelenght we can use the sin function to obtain the diameter through the equation sin(theta)= 1.22*wavelength/d where d is the diameter of the nucleus and theta is the angle of the straight through posistion to the first minimum. This bit is somewhat easier to explain with a diagram. The 1.22 may sound a little arbitrary but it does have it's basis in reasonably complex physics, 

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