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1 Atomic Physics, Nuclear Physics and Radioactivity: Example Problems with Solutions ATOMIS PHYSICS DISCOVERY OF THE PARTS OF THE ATOM: ELECTRONS AND NUCLEI 1.Rutherford found the size of the nucleus to be about. This implied a huge density. What would this density be for gold?Nucleus diameter = 10-15m Gold mass = 197 amu 1 amu = 1.66 x 10-27kg Solution2.In Millikan’s oil-drop experiment, one looks at a small oil drop held motionless between two plates. Take the voltage between the plates to be 2033 V, and the plate separation to be 2.00 cm. The oil drop (of density ) has a diameter of. Find the charge on the drop, in terms of electron units.Solution m10153g/cm0.81m100.4616nC101.6C102.6eqnC102.6qV2033m102m/s9.8kg102.71qVdgmqgmdVqWFkg102.71m6m104.0πkg/m810mdπ61ρm8dπ34ρ2dπ34ρrπ34ρρV mgmWdVE;EqFelectrons-19-18electrons-182-2-14e-1436-3333dropoil3edropoil320346-25-3-1625-3-16-25-27kg/m106.5ρm105kg103.27ρm10534kg103.27ρr34mρVmρρV mm105rkg103.27mkg/amu101.66amu197m