Question

When alpha-rays hit a thin gold foil very few alpha-particles are deflected back. what does it prove?​

Answer 1

The case of some alpha rays being deflected back by some angle means that there is some positive charge that occupies the space in an atom

Answer 2

When alpha-rays hit a thin gold foil very few alpha-particles are deflected back it proves that there is a presence of positively charged particles in that region
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as alpha particles are positively charged particles for them to defect from a region it also should have positive charge

as like charges repel each other