[[Electric Force, Field, and Potential]]
# Summary
* Net charge changes only when charge travels in and out of a system.
* Charging usually happens through electron transfer.
* Induced charge separation polarizes an object without contact. Happens in neutral conductors and insulators.
* In conservation problems, charge of separated objects should sum to charge of system.
* Grounding occurs when a system connects to a large neutral object.
* Conductors let electrons move easily, insulators only let bound charges shift slightly.
* Main 3 ways to charge: friction induction contact.