Day 102: A Visual Model for Polarization of Conductors
AP Physics C: This works best on an overhead projector(!). Take 2 pieces of colored cellophane or glass filters that are the same size. The blue represents the mobile sea of negatively charged electrons. The red represents the stationary positively charge atomic cores (nuclei).
Then place the electron sea on top of the atomic cores to represent a neutral conductor. Notice it’s black.
The electron sea shift slightly in the presence of a charged object (slide the blue filter), causing one side to become positively charged and the other side negatively charged.
I like this because it shows that the conductor as a whole is still neutral. It also refutes the misconception that lots of electrons all move to one side. In reality, it’s just a slight shift in the sea of electrons.