Principles of Electricity Electric Charge and Force Electric

Principles of Electricity: Electric Charge and Force

Electric Charge • Protons- (+) positive electric charge • Electrons (-) negative electric charge Just as in magnetism, in electricity: • Charges that are the same repel each other • Charges that are opposite attract

Magnetism vs. Electricity Magnetism • Interaction between magnetic poles • A single magnetic pole CANNOT exist alone Electricity: • Interaction between electric charges • Electric charges CAN exist alone

Electric Force • the attraction or repulsion between electric charges

Features of a circuit • Have devices that run by electrical energy • Source of electrical energy • Connected by conducting wires

Open/Closed Circuits • Open = Incomplete circuit 1. No energy can run • Closed = Complete circuit 1. Energy can follow a path

Types of Circuits • Series circuit only one path for electricity to follow • Parallel circuit more than one path for electricity to follow

The symbols for the various components are as follows: • Light bulbs • Switch R 1 • Wires • Voltage Source V V + -

Put it all together • Now that you know what the parts are, let’s draw a series circuit and a parallel circuit.

What is current? • Continuous flow of electric charges through a material (wire) • Two factors that affect current: conductors and insulators

Ohm’s Law • Ohm’s Law states that there is a relationship between current, voltage, and resistance • V = IR • Voltage = Current x Resistance

Conductors • Materials that transfer electric charge well • What kinds of materials do you think would make good conductors?

Conductors • Metals

Insulators • Materials that transfer electric charges poorly • What kinds of materials do you think would make good insulators?

Insulators • Nonmetals