Electrostatics

All electrons have the same amount of negative charge; all protons have a positive charge equal in magnitude to the negative charge on the electron

• Electrical forces arise because of the way that like charges repel and unlike charges attract.

• Electric charge is conserved

• According to Coulomb’s law, the electrical force between two charged objects is proportional to the product of the charges and inversely proportional to the square of the distance between them

Electrons move easily in good conductors and poorly in good insulators

• Objects become charged when electrons move onto them or off of them

• Charging by friction occurs when electrons are transferred by rubbing

• Charging by contact occurs when electrons are transferred by direct contact

• Charging by induction occurs in the presence of a charge without physical contact

• Charge polarization occurs in insulators that are in the presence of a charged object