Friday, 23 August 2013

WHAT MATERIALS CAN ELECTRICAL ENERGY FLOW THROUGH???

Friday, August 23rd, 2013


AGENDA

1. scribe posts - labels
2. Investigation   KEY - qualitative, energy flow
3. What materials can electrical energy flow through?
4. Vocabulary Games


Review of the "Burning puffed biscuits and potato chips experiment" 
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insulator: electrical energy cannot go through it
 ex) wood, rubber, plastic...
 conductors: electrical energy can go through it (can pass)
 ex) metals - copper, iron...



MORE INFORMATION:

http://www.fplsafetyworld.com/?ver=kkblue&utilid=fplforkids&id=16185 http://www.bbc.co.uk/bitesize/ks2/science/physical_processes/circuits_conductors/read/2/



Investigation Experiment


What materials can electrical energy go through?


Safety

  • Do not eat any of the materials.


Background information:


  • Electrical energy flows through some materials easily.  Other materials, it doesn’t flow through.





The electrical energy will flow through metals.  The energy will not flow non-metals such as plastics, rubber, wood and other insulators.



Materials & Prediction:
Equipment
  • tray
  • 2 alligator clip wires
  • battery
  • battery holder
  • ammeter



Procedure/Method:


  1. Connect objects to the alligator clips wire.  
  2. Touch those objects to the terminal of the battery that does not have alligator wire attached.
  3. Record your observations as conducts if the needle moves.  Record your observation as insulates if the needle does not move.  Record the reading on the ammeter.
  4. Repeat steps 1 to 3 for all the objects.





first of all, we prepared the materials,























We had to figure out what were the materials that electrical energy can pass through, and fill in the chart below.


Material
Conducts (C) or Insulates (I)
Write C or I below.  
Optional: explain why.
pen
I (because electricity doesn’t flow through plastics)
pencil
I
motor
C
pyrite
C- looks like a metal
graphite
I
quartz
I
Aluminum bar
C
wire with copper exposed
C
wire completely insulated
I
rubber hose
I
rusty nail
C
paper clip - large
C
spring
C






Observations:

a) Raw Data


Material
Conducts (C) or Insulates (I)
Reading on the Ammeter
/ A
Qualitative (describe observations using words and NOT numbers)
pen
I
0
plastic
pencil
I
0
wood
motor
C
0.1
- the motor spun,
- if the motor spinning was held, the reading on the ammeter increased!
- a humming sound
pyrite
C
0.4
the more the alligator clip was pushed on the pyrite, the more the current was
graphite
C
3+, 1.8
the needle moved a lot
quartz
I
0
white rock
aluminium bar
C
3+
the terminals heat up a little
wire with copper exposed
C
3+
the terminals heat up a little
wire completely insulated
I
0
- if the clips are touched to the little bit of wire inside the insulation and the wire is touched to the terminal, it will read a current
rubber hose
I
0
rubber
rusty nail
C
3+
- needle would move
- if the place where the alligator clip is attached, the reading would be different
paper clip
C
> 3
the terminals heat up a little





Using the ammeter, we checked if the electrical energy can pass through the materials given.























This one showed on the image was a paper clip.














































WORKING ON THE EXPERIMENT!!!


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Conclusion:
The purpose of our conclusion is
    • to summarize the results and
    • to compare the results to the prediction.
  1. Which materials were conductors and which were insulators?  Which results agreed with the prediction?  Which results did not agree with the prediction?

The following materials were conductors and agreed with the predictions: paper clip, rusty nail, wire with copper exposed, aluminum bar, pyrite and the motor


The following materials were insulators and agreed with the predictions: rubber hose, insulated wire, quartz, pencil and pen


The materials that did not agree with the prediction were: the graphite conducted electricity even though it’s not a metal, the rusty nail would not conduct electricity if the wires were connected to the rusty parts



  1. Why did some results - if any - not agree with the prediction?

    All metals conduct electricity, but maybe some non-metals can conduct electricity too.

    1. What were the energy changes involved in the
      1. the motor?
    electrical → kinetic of the motor,  sound (& thermal)

      1. the paper clip? (challenge - optional)
    electrical → thermal

    Evaluation (challenge):
    The purpose of our evaluation is to
      • to improve the procedure.
      • to suggest the next investigation.

    1. Is there any way the procedure can be improved so that the experiment is easier to follow?
    A picture of the experimental set-up can be included to show how the parts of the circuit are connected.


    1. Describe another investigation regarding electrical energy.  
    Could change the number of batteries and measure the current.

    Optional Challenge: Write down what would be the independent, dependent and control variables.

    Variables:
    Independent (the one that the experimenter chooses)
    • # batteries
    Dependent (changes depending on the independent)
    • current
    Control a) constants
    • wiring,


    Discussion
    1. Did anything surprise you?
    Yes, the graphite conducted electricity.  I predicted it wouldn’t

    1. Did you try any other materials - what were the results?
    I tried my hand and no current was measured.


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Mr. Pro told us that the QUALITATIVE DATA was especially important.We finished most of the process, but we couldn't go over the observations that we made together, or do the vocabulary games because we were out of time. The conclusions above was used after we went over the answers in the next class.








TO BE CONTINUED......






Today's Scribe: Silvia Lee :)











2 comments:

  1. Include how to do scribe labels in your post.

    ReplyDelete
  2. Include the skill of how to use an ammeter.

    ReplyDelete

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