Question

Draw a schematic arrangement of the Geiger Marsden experiment. How did the scattering of `alpha` particles by a thin foil of gold provide an important way to determine an upper limit on the size of nucleus? Explain briefly.

Answer 1

Schematic arrangement of the Geiger - Marsden experiment :

Observations :
(i) Since, most of the `alpha`-particles passed underviated, the atom has a lot of empty space in it.
(ii) Since, 1 in about 8000 `alpha`-particles is deflected through `180^(@)`, the size of the nucleus is about `1/10000` th of the size of atom.