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A proton is red directly at a gold nucleus. When the proton is a distance d1- : 10'r'n1 from the gold nucleus, it has a velocity '11:; : 6.0 x 104?. The gold nucleus has a charge equal to that of 79 protons and a radius of 5.0 x 1015111. You Illay treat the proton as a point charge. How close does the proton approach the nucleus? You can assume the gold nucleus is stationary the entire time