Its something that I should be able to figure out easily but my brain is refusing to work this term. So any help will be appreciated. In a scattering experiment, gold nuclei (Au Z=79 A=197) are bombarded by alpha particles (He Z=2 A=4) If the Kinetic Energy of the apha particles is 7.68MeV calculate the height of the Coulomb Barrier in MeV, and the distance between the alpha particle and the barrier when the particle collides with the barrier. So can anyone help. I should really be able to do this but my brain is goo, my fault for giving myself an easy summer.