Answer:
Ernest Rutherford
Step-by-step explanation:
Rutherford wasn't convinced about the model of the atom proposed by Thomson, therefore he set up an experiment, now called The Gold Foil Experiment. Basically he fired positively charged alpha particles at the gold foil. The he measured the deflection as the particles came the other side. Most of the particles didn't deflect at alll and every then and now a particle would deflect all the way bacx. Thus he said there must be a positive centre of the foil. Calling "5he centre" the nucleus.
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