Why don’t you try to look up Ernest Rutherford? I hope I’ve got the name right, it’s been a while since I’ve studied this stuff.

That will tell you something about the plum pudding model.

And think a bit about the two; in the plum pudding model, the positively charged portion of the atom is spread out throug the total volume of the atom. In the planetary model it is compressed into a very small portion of the center. This has implications for those who are using atom smashers (particle accelerators).

In fact, it was such experiments that led physicists to understand the concept of the atomic nucleus at all.

Look that sort of stuff up and you’re bound to come up with answers that will satisfy your teacher.