Rutherford scattering experiment

[einstein1921]

Hi,everyone!I have a problem!As known to us all,in Rutherford scattering experiment α rays are used to bomb gold foil, and most of them pass through the gold foil.But today I read something about the characteristics of α particles,the book says that you can stop α rays with a piece of paper. However,If you can stop it with a piece of paper,how can it go
through the gold foil! Your help would be highly appreciated.

 

[mfb]

The gold foil (<1µm) is thinner than the paper (~100µm).

 

[einstein1921]

The gold foil (<1µm) is thinner than the paper (~100µm).

Thank you,mfb.I get it!