What is length of gold foil paper in rutherfords theory?

In Rutherford's gold foil experiment, the gold foil used was extremely thin, with a thickness of about 0.0004 centimeters (or 400 nanometers). This allowed alpha particles to pass through and provided crucial insights into the atomic structure, leading to the discovery that atoms have a dense nucleus at their center. The experiment fundamentally changed the understanding of atomic models, shifting from the plum pudding model to the nuclear model of the atom.