Monday, December 20, 2010

Circuit Review

Today we started by going over the homework.
For the first lab or sim:
A hand causes an open circuit
Metals causes an closed circuit
Metals' have electrons that want to move
Our bodys have electrons but they don't want to move

electrons- things that circle around atoms

When we rub a ballon/ plastic parachute against somebodys hair, what happens?
- a transfer of electrons

Why does the hair stick up straight?
- Persons hair has alot of electrons, ballon none, so ballon or plastic parachute was attracted to the hair because it had a different charge. The hairs repel each other beecause they have the same charge. Zak got all of the electrons because we rubbed the plastic against his hair.

Why does the lightbulb light?
-The battery pushes the electrons through the wire
- It goes into the filament
- The filamwnt gets gets warmer through the electrons and releases light

What happened to the electron motion with 2 wires and 1 battery?
They electrons moved really really fast, that it made the battery lit up in fire.

When you add a lightbulb, what happens?
The lightbulb transforms the kinetic energy from the electrons into the light energy.

When you hold a piece of black paper close to a light bulb it gets hot because light energy was transfered into internal energy.

Inside of the filament the elecrons are bumping against each other, creating the light.

Kathleen then used a hammer to break a light bulb. The filament and and based were then passed around to figure out where the two wires went to into the base.

Light Bulb Diagram:
3. filament
4. (green wire) allows electrons to enter the bulb
5. (blue wire) allows electrons to leave the bulb

The green wire goes to the bottom of the bulb and the blue wire goes to the metal.

We then watched a video.
Video notes: Vocab
Parrel Circuit- when there is an additional track and when one is blocked you can still use the other.
Series Circuit- when there is only one track
LED- light emitting diode
Direct Current- electrons are all going in the same direction (DC)

Then in middle of the video the bell rang, so we stopped.

Media :
Youtube Videos:
1. http://www.youtube.com/watch?v=apHkG4T6QHM - Series Circuit v. Parallel Circiut

2. http://www.youtube.com/watch?v=JZjMuIHoBeg - DC v. AC (we don't need to know AC)

3. http://www.youtube.com/watch?v=YnMP1Uj2nz0 - How a filament works


Enjoy!

Homework for tonight is to study!
STUDY! STUDY! STUDY!
STUDY SESSION TOM. AT 7 AM!
TEST ON ENERGY IS TOM.
STUDY GUIDE ON FIN'S WEBPAGE:
http://www.npsd.k12.nj.us/20222069133223760/blank/browse.asp?A=383&BMDRN=2000&BCOB=0&C=59194

Personally I find that this electricty/ circuit stuff is pretty easy. The only thing that still confuses me is the many diferent circuits and current types. Also the difference between a current and a circuit is confusing. They said the definition for current in the video, but I was typing a different definition, and when I got to it, had forgotten the meaning and was typing the next one. I'll probably find out what it means when we watch the video some more on Wenesday, because we can't watch it on Tuesday due to our test.

DB

8 comments:

  1. Daphne I have a question. I know LED stands for light emiting diode but what is a diode?

    KS

    ReplyDelete
  2. The dictionary.com definition is:
    –noun Electronics .
    a device, as a two-element electron tube or a semiconductor, through which current can pass freely in only one direction.

    which from what I can tell is a device that lets the current be a direct current.
    DB

    ReplyDelete
  3. If a circuit has one light bulb and 1 battery and we increase the amount of wire, does the brightness of the light bulb change?

    ReplyDelete
  4. Zak, the brightness of the light will not change because it is the same amount of energy going to the light bulb, but just a little farther away from it. the battery is the same and the light is the same.

    ReplyDelete
  5. Wait, can you include a key-thing for the diagram? I didn't get the names of them.
    EL

    ReplyDelete
  6. what would happen if you held up white paper instead of black paper to the lightbulb?
    -EP

    ReplyDelete