1. Static Electricity It’s electrifying!

2. Parts of an atom Electron Negatively charged Proton Positively charged Neutron Neutral

3. Only electrons are free to move from one atom to another. Protons and neutrons are tightly bound in the nucleus. A neutral atom has an equal number of protons and electrons. An atom with more electrons than protons is negatively charged, and an atom with fewer electrons than protons is positively charged. The presence of an electric charge is detected with an electroscope. There are several types of electroscopes. We will use the pith ball and metal leaf electroscopes.

4. Law of Electrostatics Like charges repel, unlike charges attract.

5. Types of Substances Conductors—electrons flow freely (metals) Conductors—electrons flow freely (metals) Insulators—electrons are tightly bound in place (glass, rubber) Insulators—electrons are tightly bound in place (glass, rubber)

6. Ways to charge a substance Conduction—actual transfer of electrons from one substance to another Conduction—actual transfer of electrons from one substance to another Induction—polarizing the charge within a substance. Induction—polarizing the charge within a substance. An electrophorus plate is an example of something that charges by induction.

7. Coulomb’s Law Where F = force k = Coulomb’s constant (8.99 x 10 9 Nm 2 /C 2 ) q 1 and q 2 = charges in Coulombs r = the distance between q 1 and q 2

8. Sample problem Two electrons (q = 1.6 x 10 -19 C) are separated by a distance of 0.2 meters. What is the force between them, and is it attractive or repulsive?

9. Van de Graaff Generator

10. Wimshurst Generator