Van de graff generator gives the same current. How?

In summary, the reason why we don't die when we touch a Van de Graff generator is because it acts as a current source with very low constant current. This is due to its similarity to a charged capacitor, where the voltage drops dramatically at discharge and builds up again. However, there is some debate over whether it can be truly considered a current source.
  • #1
iVenky
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The reason why we don't die when we touch a Van de Graff generator is because it produces a very low constant current and when you touch it only the voltage change and not the current. It's like a current source rather. But how does that produce constant current?

Thanks in advance.
 
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  • #2
It's like a current source rather. But how does that produce constant current?

It's more like a charged capacitor...one with high voltage and very low current...

Now that you mention it, I don't think I've seen an equivalent circuit for one...

edit: I just checked wikipedia and they have a different perspective..."Since a Van de Graaff generator can supply the same small current at almost any level of electrical potential, it is an example of a nearly ideal current source."

http://en.wikipedia.org/wiki/Van_de_Graaff_generator

If I recall the voltage drops dramatically at discharge... before buiilding again...more like a capacitor, but it's arguable...
 
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Related to Van de graff generator gives the same current. How?

1. How does a Van de Graff generator give the same current?

A Van de Graff generator works by using a moving belt to transfer electrical charge from a large metal sphere to a smaller metal sphere. This process creates a high voltage potential between the two spheres, which allows for a steady flow of current to be produced. This current remains constant because the amount of charge being transferred is the same, regardless of the size of the spheres.

2. What is the mechanism behind a Van de Graff generator producing the same current?

The mechanism behind a Van de Graff generator producing the same current is based on the principle of conservation of charge. This means that the amount of charge in a closed system cannot change. As the belt transfers charge from the larger sphere to the smaller sphere, the amount of charge on each sphere remains constant, resulting in a constant current being produced.

3. Does the size of the spheres in a Van de Graff generator affect the current produced?

Yes, the size of the spheres in a Van de Graff generator can affect the amount of current produced. The larger the spheres, the greater the surface area available for charge accumulation, which can result in a higher current. However, the amount of current produced will remain the same as long as the charge being transferred remains constant.

4. Can a Van de Graff generator be used to produce a variable current?

While a Van de Graff generator is primarily used to produce a constant current, it is possible to vary the current by adjusting the speed of the belt or the distance between the spheres. However, this method is not recommended as it can cause damage to the generator and is not an efficient way to control current.

5. Is the current produced by a Van de Graff generator safe?

The current produced by a Van de Graff generator can be dangerous if proper precautions are not taken. The high voltage potential can cause electric shocks and can be fatal in extreme cases. It is important to follow safety guidelines and use protective equipment when working with a Van de Graff generator.

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