This Unit's |
Process Standards: 1.1, 3.3, 3.5,
4.1, 5.2, 6.1, 6.4 Content Standards: 1.1, 2.1, 3.1 Instructional Technology Standards: 2.1, 4.2 |
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While these particles are usually thought of as electrons, any charged
particles will do.
Read the historical beginnings
of the theories of electricity and magnetism.
| What happens when an object with an excess of electrons touches a neutral object? |
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Electric
charge is defined by subatomic particles. Electrons and protons have
opposite charge properties. Electrons are assigned a negative charge (-) and
protons a positive charge (+). In normal atoms, there are equal numbers of each
of these particles, giving the atom a "neutral" electric charge over all.
While changing the number of protons in an atom is very difficult, atoms gain or loose electrons relatively easily. When an atom gains electrons, there are more electrons than protons and the atom will have a "negative" charge over all. When an atom looses electrons, there are more protons than electrons and the atom will have a "positive" charge over all.
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Electric field: An area around a charged particle in which forces of attraction or repulsion are noticeable.
Static electricity:
Electricity with high voltage and low power output.
Charge can be transfered by:
Computer Assignment 301:
This assignment must be completed by the end of class today to receive credit.
Scoring criteria![]()
Use Powerpoint to graphically show the following:
Show the slide to your science facilitator when finished.
- A flat, circular, positively charged containment field is established.
- Three protons are placed into this containment field.
- Where are the protons in this field?
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Any volunteers may ask the science facilitator for a Van de Graaff Generator and try your luck producing static electricity. |
| Power poles carry either one, two, or three electric lines. What is significant about the different numbers of lines? |
Electric current: Electricity with high power
output and low voltage.
2
types of electric current:
Direct
Current, DC: current flows in one direction only.
Alternating Current, AC: current flow changes direction.
| Why does a battery stop producing electricity? |
Electrician |
Conductors: Materials that easily allow
the flow of an electric current.
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Insulators: Materials that do not easily allow the flow of an electric current.
Voltage: The electric potential difference between two points.
Ampere: A measure of the amount of current flowing past a given point per second.
| Amperes = Volts / Ohms |
Ohm: A measure of the resistance to
the flow of current.
There
are four factors that determine the resistance of a material:
Ohm's Law: The current in a wire is equal to voltage divided by resistance.
| Current = voltage / resistance |
Electrochemical cells changes chemical energy into electrical energy. Whether wet or dry, these cells provide a source of charged particles.
| Wet Cell | Dry Cell |
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Electric circuit: A complete, closed path for an
electric current.
There is only one path for the electrons to take. | |
There is more than one path for the electrons to take. |
Electric power: A
measure of the rate at which electricity does work or provide energy.
Power = Voltage X Current
Watts = Volts X Amperes
Energy = Power X Time
Emergency switch:
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Concept Understanding: ![]()
- Connect 4 light bulbs in a series circuit.
- Connect 4 light bulbs in a parallel circuit.
- Find out what makes an electric current fatal.
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- What characteristic of electricity causes the seriousness of an electric shock?
- What is the lowest value of this characteristic that is considered lethal?
- Compare the electrical resistance of dry skin and wet skin.
Research Links:
When an object with an excess of electrons touches a neutral object, electrons are passed to the neutral object.
Each line carries electricity in a different phase.