Today we wrapped up discussion of density and used it to discuss the size of particles. We started by observing that if our aluminum is .002cm thick, then particles must be smaller than that. The students pretty much agreed that particles must be much smaller than that. So now the question was how big??? We went through a few videos and started a sheet to help them get a mental picture of how big are atoms.
Thickness of gold leaf:
Thickness of noodles
Thickness of particles from oil on a pond