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electrical conductivity ON ELECTRICAL RESISTANCE

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					matter physics: electrical conductivity ON ELECTRICAL RESISTANCE

You have to understand that the electrical charge or electrical current can move from one place to
another because of the potential difference. But not all agents have good electrical conductivity. To
investigate the substances that are easy and difficult to be conductor of electric current do the
following activities.

Investigate electrically conductive substances
1. provide copper wire, iron wire, plastic rope, rubber, wood, paper, and a carbon rod as a liaison.
2. Also provide two batteries and light bulbs.
3. in turn change the intermediary substance. What about the flame bulbs?

Based upon the above, what about your observations of the power of the material that has been
provided.

At the time the theory of the electron, we know that electric charge can move is a negative charge
or electron. Electrons move easily are called free electrons. Conductors or conductive substances
have a lot of free electrons that can easily flow of electric current. As the insulator does not have
free electrons, electron transfer does not occur or electric current.
A substance that has properties between conductors and insulators called semiconductors.
Substances that at low temperatures is as an insulator but at moderate to high temperatures are
conductors, such as germanium and silicon. Semiconductor materials used to make transistors, the
electronic components used in radio and television.

Different Potential Effect on Electrical Conductivity
Electric current flows due to the potential difference. The greater the potential difference between
two points lead to strong currents that flow becomes greater. However, if the bottleneck through
which electric current was so strong the current is going down. Thus, the magnitude of the current
flowing strong mainly due to the potential difference (voltage) and is affected by conductor
resistance.

To clarify this, consider the following. A substance that has a very large resistance, eg 100,000 ohm,
when connected to a voltage source that has a potential difference of 12 volts, strong currents that
occur naturally very small. If the substance is associated with a very high voltage, such as 300
kilovolts, strong currents generated = 300.000/100.000 = 3 amperes. It shows that the substances
are insulators when connected to a high potential difference will be the conductor.

So a little explanation of the electrical conductivity of the electrically conductive. Hopefully these
summaries will help you understand the electrical resistance that affect the electrical conductivity.

				
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posted:10/1/2012
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