1. 8.2 - Electric
Current

2. Challenge Build a circuit that can turn on and off a light using:
3 wires
1 source
1 load
1 switch
Source = battery
Load = light

3. See page 281

4. Electric Circuits
A complete pathway that allows electrons to flow is called an electric circuit.
The circuit must have at least one source of voltage (battery or other power source).
Electrons flow through devices in the circuit that convert electricity to other forms of energy (electric loads.)
Light bulbs, motors, buzzers, heater, etc.

5. Basic Circuit Components
A circuit consists of 4 basic components:
Source: source of energy
Conductor: wire where current flows
Load: turns electricity into other forms
Switch: turns circuit on or off

6. Circuit Diagrams
See page 282

7. Draw circuit diagrams for the following circuits:B C D

8. Current Flow
Electric current is defined as the amount of charge passing a point in a conductor every second.
Current is measured in amperes (A), and can be detected with an ammeter.
Electrons (-) flow from negative to positive.
Conventional Current
In the early days of electricity research, scientists mistakenly believed that positive charges moved and electricity flowed backwards.
This is known as conventional current. (positive to negative)

9. Practice
Workbook Pages
Due: Thursday, March 2