Questions:

1. Can you account for all the forces observed with just 2 kinds of charge, or do you need a third? Please don't answer, ``Yes, and we don't need a third''. Instead, show how to account for each deflection using the two charge theory (or how this is inadequate based on your results). Comment on whether some other force can account for your observations.

2. What charge does a body have if it is attracted to both kinds of charge?
3. Consider the form of the force equation for electric charges, the physical dimensions of which are all much smaller than their separation, upon each other:
   
   $$F \propto \frac{Q_1 Q_2}{r^2},$$
   
   
   and discuss whether this is better than having $(Q_1 + Q_2)$ in the numerator.
4. Did you observe an ``inverse square law'' interaction? Do you expect to?