Question

which observation of Rutherford experiment proved that centre of the atom consists of a heavy positive charge part called nucleus

Answer 1

Rutherford made an experinment whose arrangement was ... first three was a lead which consists of alpha particles then there was a gold thin sheet and then was an atom. the made a hole in the gold sheet so as the alpha particles could pass.... on passing alpha particles he observed tagt 1 out of 12000 apha particle returned at 180° angle ...this showed that there is a heavy positive charge due to which alpha particles moved back ... because alpha particles are +ve and same charge repels each others... this proves that alpha particles repeled due to positive charge called protons....

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Answer 2

Ernest Rutherford design an experiment to check the validity of Thomson's atomic model that model is Alpha scattering experiment so in this experiment a stream of high energy Alpha particles from a radioactive source was directed at 18 fall of gold metal tin foil hat a circular fluroscent zinc sulphide screen around it an Alpha particle stuck the screen at tiny flash of light was produced at that. In this Alpha Ray scattering experiment the following observations were made that is first the most of the Alpha particles pass through the gold foil and undeflected a small fraction of Alpha particles was deflected by small angles very few Alpha particles bounced back that is there deflected by an angle nearly 180 degree