1. Both Apparatus Description and Procedure should be included in this part.
a. Apparatus: Description of Rods & Cloths.
b. Procedure: Rub, Charge the Electroscope, Discharge the scope by touching the ground using the grounding metal (not our hands).
2. Measurement: Controlling Group
Don't forget the controlling group: when there's no charge, the opening angle between the arms might not be zero due to systematic effects. In this step, you have to use the grounding metal to touch the electroscope to make sure that there is no charge; the rods may have charges before rubbing, so touch them with the grounding metal first.
3. Measurement Comparison
Develop a system for comparison: the magnitude of the charge is determined by the angle between the two arms of the electroscope.
4. Data Tables
a. Table Legend: legend should be included and placed above a table.
b. Decimal Places: one. Even for "0" measurement, you should report that in "0.0".
c. Complete set of combinations, otherwise you will get 1 point.
5. Results (Models)
a. The model of positive/negative charge should be proposed. Example: our hypothesis is that there are two different kinds of charge, which can be tested by the following procedure.
b. Testing the model: leave the electroscope charged (i.e., setting a reference "positive" charge), and touch it with another rubbed rod -- if the angle increases (decreases), they have the same (opposite) charge.