1. Basics of Electricity Electricity Gateway To Technology®
Unit 4 – Lesson 4.1 – What is Electricity?
Basics of Electricity

2. What is Electricity? Involves the movement of electrons Is invisible
Gateway To Technology®
Unit 4 – Lesson 4.1 – What is Electricity?
What is Electricity?
Involves the movement of electrons
Is invisible
Provides light, heat, sound, motion . . .
Has been practical for use over the last 100 years

3. History 2500 years ago, the Greeks rubbed amber with other materials.
Electricity
Gateway To Technology®
Unit 4 – Lesson 4.1 – What is Electricity?
History
2500 years ago, the Greeks rubbed amber with other materials.
They discovered that this process would attract feathers and other lightweight materials to the amber.

4. . . .opposite charges attract and like charges repel.
Electricity
Gateway To Technology®
Unit 4 – Lesson 4.1 – What is Electricity?
History
. . .opposite charges attract and like charges repel.
Ben Franklin suggested that . . . + -

5. . . .opposite charges attract and like charges repel.
Electricity
Gateway To Technology®
Unit 4 – Lesson 4.1 – What is Electricity?
History
. . .opposite charges attract and like charges repel.
Ben Franklin suggested that . . .
The Law of Charges explains why the electrons continue to be bonded to the nucleus.
The law of charges was first discovered by Charles Augustin de Coulomb. It explains that all magnetic objects have the tendency to repel or attract to one another. Like charges repel one another and unlike charges attract one another. The attraction or repulsion occurs in a straight line, there is a force between the charges and the bigger the charges the greater the force. + +

6. Electricity
Gateway To Technology®
Unit 4 – Lesson 4.1 – What is Electricity?
Electron Flow
An electron from one atom can knock out an electron from another atom.

7. Electricity
Gateway To Technology®
Unit 4 – Lesson 4.1 – What is Electricity?
Electron Flow
Electricity is created as electrons collide and transfer from atom to atom.
Play Animation

8. What Makes Up Electricity?
Gateway To Technology®
Unit 4 – Lesson 4.1 – What is Electricity?
What Makes Up Electricity?
Let’s compare it to something we know --- Water!

9. Water Analogy Tank = Battery Pipe = Wiring Faucet = Switch Tank Faucet
Presentation Name
Gateway To Technology®
Unit # – Lesson #.# – Lesson Name
Water Analogy
Tank
Faucet
Pipe
It might be necessary to remind students what an analogy is.
Tank = Battery
Pipe = Wiring
Faucet = Switch

10. Current Current: The flow of electric charge Tank (Battery)
Presentation Name
Gateway To Technology®
Unit # – Lesson #.# – Lesson Name
Current
Current: The flow of electric charge
Tank (Battery)
Faucet (Switch)
Pipe (Wiring)
It might be necessary to remind students what an analogy is.
When the faucet (switch) is off, is there any flow (current)? NO
When the faucet (switch) is on, is there any flow (current)?
YES

11. Current in a Circuit When the switch is off, there is no current.
Presentation Name
Gateway To Technology®
Unit # – Lesson #.# – Lesson Name
Current in a Circuit
off on
off on
When the switch is off, there is no current.
When the switch is on, there is current.

12. Voltage Voltage: The force (pressure) behind the flow of current
Presentation Name
Gateway To Technology®
Unit # – Lesson #.# – Lesson Name
Voltage
Voltage: The force (pressure) behind the flow of current
Tank (Battery)
Faucet (Switch)
Pipe (Wiring)
When the faucet (switch) is off, is there any pressure (voltage)?
YES – Pressure (voltage) is pushing against the pipe, tank, and the faucet.
When the faucet (switch) is on, is there any pressure (voltage)?
YES – Pressure (voltage) pushes flow (current) through the system.

13. Presentation Name
Gateway To Technology®
Unit # – Lesson #.# – Lesson Name
Voltage in a Circuit
off on
off on
The battery provides voltage that will push current through the bulb when the switch is on.

14. Resistance Resistance: The opposition to the flow of current.
Presentation Name
Gateway To Technology®
Unit # – Lesson #.# – Lesson Name
Resistance
Resistance: The opposition to the flow of current.
Tank (Battery)
Faucet (Switch)
Pipe (Wiring)
All materials have resistance. Conductors have little resistance. Insulators provide a lot of resistance. Some electronic components (resistors) have a specific resistance. These are often needed to reduce current in order to protect other components or to adjust the amount of current that goes to other components.
What happens to the flow (current) if a rock gets lodged in the pipe?
Flow (current) decreases.

15. Resistance in a Circuit
Presentation Name
Gateway To Technology®
Unit # – Lesson #.# – Lesson Name
Resistance in a Circuit
Resistor
off on
Resistors are components that limit the flow of electricity.
Reducing current causes the bulb to become more dim.

16. (You might already know these!)
Types of Electricity
(You might already know these!)

17. Types of Electricity Static Electricity Current Electricity
The electrical charge an object develops as a result of having an unequal number of protons and electrons.
(Static Electricity) When the imbalance of charge becomes too great, the electrons will move.
(Current Electricity) The movement happens when a push (voltage) is applied to the electrons.
Current Electricity
The movement of electrons through a conductor.

18. Static Electricity Uncontrollable Electricity Lightening Static Cling
Wool socks on a carpet “shocks”

19. Alternating Current (AC)
Current Electricity
Two Types:
Direct Current (DC)
Alternating Current (AC)

20. Direct Current
The electrons flow in the same direction all the time, from negative to positive.

21. Direct Current Comes from Batteries Converted from Alternating Current
Used for electronic devices including
Computers
iPods
Cell phones
Anything that has a “charger”
Batteries provide current electricity through a chemical reaction. In today’s activity students will “build” a DC battery.
Anything that has a cord with a “box” attached to the cord is converting AC current to DC current.
Show examples of cords with converter boxes.
Demonstrate using the multimeter to measure the voltage of the battery. Show how switching the leads from the multimeter on the battery changes the + or - sign in the display. This happens because DC voltage is directional. Black lead to negative and red lead to positive will show a positive voltage. Black lead to positive and red lead to negative will give a negative voltage. (This will help students answer the Conclusion question #2 in the next activity.)

22. The electrical current (movement of electrons) changes direction.
Electricity
Gateway To Technology
Unit 6 – Lesson 6.1 – What is Electricity?
Alternating Current
The electrical current (movement of electrons) changes direction.

23. Alternating Current Comes from Generators
Electricity
Gateway To Technology
Unit 6 – Lesson 6.1 – What is Electricity?
Alternating Current
Comes from Generators
Coal burning and nuclear power plants
Hydroelectric power plants
Wind and solar generators
Used for
Motors
Heaters
Lights
Anything that plugs into the wall

24. Electricity
Gateway To Technology®
Unit 4 – Lesson 4.1 – What is Electricity?
Image Resources
Microsoft, Inc. (2008). Clip Art. Retrieved September 10, 2008, from