2 Laws of Static Charges
Law of attraction = particles with opposite charges attract each other
Law of repulsion = particles with “like charges” (same charges) repel each other

• When an object is charged, it stays that way until the electrons have a path to escape
• When charges are transferred VERY quickly this is called ELECTRICAL DISCHARGE
• Sparks are an example of this
• Lightning is an a VERY large electrical discharge
• The air becomes a passage for electrons to travel and causes a spark

What makes the light and Crackling
Sound during a spark?
- Collisions between air particles and moving electrons!
- when your negatively charged hand reaches for the neutral doorknob, the excess electrons transfer due to induction

GROUNDING
• Removing excess charge on an object through electron transfer
• Connecting a charged object to the Earth’s surface
- When you connect a charged object to the ground = a path for charges to travel to and from the ground

Electrical Insulators and
Conductors
Insulators: resists or blocks movement of electrons
Ex: wood, rubber, plastic
Conductors: allows movement of electrons through
Ex: copper and aluminum

Triboelectric
Series

- The tendency of a substance to hold onto electrons
Using the Electrostatic series, how can we determine which charge will the following substances get after they have been rubbed together?

Ebonite Rod and Fur

CHARGING BY FRICTION
• two objects rub together , the force removes electrons from one object and transfers them to the other object
• Object that lost electrons = positively charged
• Object that gained electrons = negatively charged

CHARGING BY CONTACT

CHARGING BY INDUCTION

Grounding the Object Using a Water
Tap or your Finger

• A Dercho
• Investigating Science 9 -Pearson