The structure of an atom is a fixed core of protons and neutrons with electrons orbiting around the exterior. Protons have a "positive" (+) charge. Electrons have a "negative" (-) charge. Neutrons are not charged, therefore they are neutral. The charge of one proton is equal in strength to the charge of one electron. When the number of protons in an atom equals the number of electrons, the atom has no charge, and is neutral. If there are more protons than electrons, the atom has a positive charge. When there are more electrons than protons, the atom has a negative charge. As electrons pass between atoms, it forms electricity.
There are two types of electricity: static electricity and current electricity. Current electricity is the flow of electrons between a sink and a source, with a continuous difference. This type of electricity travels through conductors. Conductors are anything that allows passage easily. Static electricity is repetitive one-time charges and discharges.
A circuit is a closed loop of conductors for electricity to flow through. To make a circuit, you must have a load, which uses power, a source, which provides power, and a conductor, which transfers the electricity. In the first five labs, the load was the light, the source was the battery, and the conductor was the wire connecting the two.
Load arrangement affects voltage and amperage depending on its amount and circuit type. In a series circuit, the less load, the higher the total amperage and voltage will be. Amperage stays the same everywhere in a series circuit, while voltage divides up between each load. In a parallel circuit, the further the load is from the source, the lower the amperage will be. Voltage stays the same throughout every spot in a parallel circuit.
The third lab measured amperage and voltage in series and parallel circuits with two sources. When the sources were arranged in parallel, the light was about the same brightness as it would have been if there had only been one source.