Static electricity and high voltage?

AI Thread Summary
Static electricity generates high voltage due to the difference in charge between objects, such as a person and the ground. This difference creates an electric field that can ionize air, allowing charge to transfer to an oppositely charged object. A high electric field strength, around 1kV/mm, is necessary for noticeable effects like sparks. The voltage can vary significantly, from the charge of a single electron to millions of volts in specialized generators. Understanding these principles can be enhanced by studying resources on static electricity and electrostatics.
Taylor_1989
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I was just wondering how static electricity has a high voltage. Is it because of the difference of charge between the two objects e.g you and the ground?

Or is it due to the electric field which surrounds an static charged object, so the electric field cause ions to build in the air allowing the charge to travel across to an object of opposite charge, i.e the longer the electric field is allowed to create ions the more voltage?
 
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Is it because of the difference of charge between the two objects e.g you and the ground?
Different charges on different objects can generate a field in between. Where "different charges" may include non-trivial computations to get the voltage for specific problems.

Or is it due to the electric field which surrounds an static charged object, so the electric field cause ions to build in the air allowing the charge to travel across to an object of opposite charge
You need a really high field strength to get this, something like ~1kV/mm. This can happen if you touch good conductors, which generates a small spark.
 
Taylor 1989, From your questions I guess that you are beginning your studies of electricity. Static electricity is, as you say, the difference in potential between two objects and is measured in Volts. The amount of charge differences can be over the whole range from the smallest (that would be one single electron's charge) difference all the way up to Millions of Volts difference in some special generators.

I suggest you read and study these two Wiki pages first:
http://en.wikipedia.org/wiki/Static_electricity
http://en.wikipedia.org/wiki/Electrostatics

In the second one you will see a diagram that I think is excellent for visualizing what electrostatic charged objects would look like if we could see the charge distribution:
http://en.wikipedia.org/wiki/File:Electrostatic_induction.svg

Finally, for tons of fun, you could build a "Kelvin Water Dropper" which uses drops of water to transfer charge. Quite high Voltages can be made with this simple device anyone can make at home or in the lab.
http://www.eskimo.com/~billb/emotor/kelvin.html

If you have more questions or some doubts, come right back here and post them!
Cheers,
Bobbywhy
 
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