Electric Charge Basics
What is static electricity?
The buildup of electric charges on an object's surface.
What is charging by friction?
Electrons are transferred when objects are rubbed together.
What is a conductor? Give an example.
Allows electrons to move easily, e.g. metal.
What is an electric discharge? Give one example.
The sudden release of static charge, e.g., a spark, lightning, or shock.
Give one example of static electricity in everyday life.
Rubbing a balloon on hair, clothes sticking in the dryer, or a shock after walking on carpet.
What moves between objects to create charge?
Electrons.
How do you use the electrostatic series?
The higher material loses electrons, the lower gains them.
What is an insulator? Give an example.
Restricts electron flow, e.g. plastic.
How is charge built up and released in a Van de Graaff generator?
Friction transfers electrons to the metal dome → the charge builds up → discharges when touched or grounded.
How does fabric softener use static electricity?
It reduces friction and adds moisture, preventing charge buildup so clothes don’t stick.
What happens between two objects with like charges?
They repel each other.
What is charging by conduction?
Transferring charge by direct contact.
Why can water be both an insulator and conductor?
Pure water is an insulator, but tap water conducts electricity because it contains ions and minerals.
Describe what happens during lightning in the clouds.
Charge separation occurs — the bottom of clouds become negative, ground becomes positive, and electrons jump to the ground as lightning.
Explain how a pith ball can be charged.
Touching it with a charged object transfers electrons by conduction or induction.
What happens when a charged object touches a neutral one?
Electrons transfer until both objects have the same charge.
How do you charge an electroscope by conduction?
Touch it with a charged object to transfer electrons.
Why are insulators used to cover electrical wires?
To prevent electric shock and stop current from escaping the wire.
What is grounding, and what is its symbol?
Grounding safely transfers excess charge to Earth. Symbol: ⏚ (a line over smaller lines).
What happens when a balloon sticks to a wall?
The balloon is charged and induces opposite charges on the wall’s surface, causing attraction.
Name the three rules of electric charges.
Like repel, opposites attract, neutrals attract charged objects.
What is induction?
Rearranging electrons in an object without touching it.
Explain what happens to electrons in conductors versus insulators.
In conductors, electrons move freely; in insulators, electrons are tightly bound and cannot move easily.
Why is Earth considered neutral, and what happens during grounding?
Earth has so many charges it stays neutral — it absorbs or supplies electrons to neutralize objects.
Describe the connection between lightning and induction.
Induction causes charge separation between clouds and ground, leading to a discharge (lightning).