Agenda Bell Work

• Pick up Static Electricity WS from front desk

• complete

• Balloons and Travoltage Activity

• Notes: Static vs. Current Electricity

HW: Chp. 11 pg 174-182

April 30, 2012

1. Define and describe static electricity2. Define and recognize the presence of a

charge3. Distinguish between conductor’s and

insulator’s4. Describe how static electricity is different

than current electricity

Movement of charged particles

Rule 1: Like charges repel one anotherRule 2: Unlike charges attract one

another

Electrons carry negative charges and protons carry positive charges

Electrons can move from atom to atom

An atom that has more electrons is negative

An atom that has less electrons is positive

The imbalance of positive and negative charges

So how do we move electrons from one place to another?

By rubbing them together

The build up of electrons creates a static charge

The jumping of electrons from one object to another creates a static shock

When two objects are attracted the atoms don’t move, only their charges

The positive part of one object will be attracted and move toward the negative charge of the other object

TRIBOELECTRIC SERIES your hand

glassyour hairnylonwoolfursilkpapercottonhard rubberpolyesterpolyvinylchloride plastic

Items near the bottom tend to gain negative charges when rubbed with something near the top

Clouds become negatively charged relative to the ground

Lightning appear as charges are exchanged between the clouds and the ground

Currents made of flowing electrons, in one direction

Ampere (A) – the rate of electrical flow

1 C of charge (6.25 billion billion) per second

So a wire that carries 5 A has 5 coulombs of charge per second

Electrons flow only when there is a difference in electrical pressure – voltage Higher the pressure (V) stronger the flow

Voltage = potential energy/charge

Wires need a pump that provides the voltage to cause flow

Simple Circuit

Have loosely held electrons that travel very easily Most metals

Materials that do not allow electrons to travel freely

Plastic, cloth, glass and dry air