Geiger and Marsden Experiment

[Ruth Rosales 3D]

I just wanted to get some more insight into the experiment that determined their model. In high school, I never understood why shooting the alpha particles to the aluminum helped them. Even with the visuals.

[Pranav Daggubati 3C]

Basically, the alpha particles, which were known to have mass, were shot into the foil. Then, Geiger and Marsden noted that some of the alpha particles bounced back even though most went through. This lead them to figure out that the foil had both empty spaces in it and it also had a certain place where the alpha particles could hit and reflect back. This meant that the atoms that comprised the foil had to have had a lot of empty space and a little voluminous space where matter existed.

[kristinalaudis3e]

They were able to discover that atoms had a concentrated mass within the nucleus (including all the positive charges) through their foil experiment because of how the the alpha particle beamed scattered after hitting foil. They found that most of the particles could go through and only a tiny fraction of them bounced off the reflector and onto the screen, but this indicated that most of the foil was empty space, but some parts of the foil had matter where the alpha particles could reflect back. I hope this helps :)