Oct. 23 – Electric Cells and AC/DC

Quiz Tomorrow!  Here's what to expect.

Knowledge Questions:

• Multiple choice and fill in the blanks.
• These questions involve basics such as Law of Electric Charges, charging, conductors, insulators, etc.

Communication Questions:

• These involve drawing charges on diagrams.
• Very similar to these questions: Electrostatic Activity

Thinking/Inquiry:

• Long Answer.
• I will ask you how to do something in a laboratory and you describe the procedures.

Good luck!

Here's today's materials.

Continue with Electric Cells

Parts of an electric cell:

 - positive terminal (cathode)

 - electrolyte

 - negative terminal (anode)

Electrons move from the anode to the cathode.

Create your own electric cell with a lemon!  Here's how:  http://hilaroad.com/camp/projects/lemon/lemon_battery.html

Then we watched this video of charging an iPhone with a watermelon and discussed why it was fake:

http://www.youtube.com/watch?v=whRyCKtxZI8

Fuel Cells

Electric cells that can operate continuously by adding fuel.

Ex: Hydrogen fuel cells in cars.  They us hydrogen to produce energy and power the car.

Advantages :)	Disadvantages :(
- when you burn hydrogen, the waste is water - no greenhouse gases - don’t have to dig up more fossil fuels	- people will not give up gasoline  - hard to find hydrogen on Earth  - highly reactive  - need to use a lot of energy to get pure hydrogen

Then we went on to discuss different forms of current electricity.

Forms of Current Electricity 

Learning Goals: Understand the difference between AC and DC electricity.

Success Criteria: You can describe the difference between AC and DC electricity.

Handout: Forms of Current Electricity

We then talked about the fact that there are two different kinds of electricity.  DC goes in one direction all the way around the circuit, while AC goes back and forth.  Both are able to carry energy and both are usefully in different ways.

FUN FACT: The band AC/DC got their name from an "alternating current/direct current" label on a sewing machine!

Then we talked about how electricity is generated.  In nature, there's an animal that can generate it's own electric field.  Have a look at this video: http://www.youtube.com/watch?v=y9wktSQdyaE

We needs more than eels to general electricity for entire cities though, so we use electric generating stations that turn other forms of energy into electric energy.

Have a read at chapter 12.4 to complete the handout.

Homework: Study for Quiz