Lab Notes: Electrostatic Phenomena
The Electrostatic Phenomena lab is intended to be done largely without preparation.
It's an education in scientific thinking.
Nevertheless, it is helpful to read over the ``especially relevant links''.
There are a few points about the lab to make too:
- The long cords on the hangers tend to cause the hangers to swing easily
with the breeze.
Pinching the hanger cord a few inches above the hanger seems to give
about the right amount of freedom to see small electric force effects without
random breeze effects.
- Rub wool on rubber and styrofoam on plastic unless otherwise directed.
- The chair covers seem to work better than the wool at charging the rods.
- One should say rubber charge and plastic charge at first.
But after the oscilloscope gives a positve and negative readings, it is
good to speak of positive and negative charge.
- Turne the field mill's off when
not using them. They are very noisy.
- Don't let wool fragments drop in the field mills.
- The metal rods may not hold a charge well if the humidity is high.
- Whether polarized neutral rod gives an increased field or a decreased seems to be
dependend on cases---or so it seemed last semester.
I think more reproduceable results are obtained using a long wire from the rack.