# Van de graff generators maximum voltage

• abdo799
In summary, the maximum voltage that a van de graff generator can achieve is determined by the sphere's radius and the electric field at which corona discharges begin to form in the surrounding gas. This means that the charge on the sphere cannot be accumulated to an unlimited amount.
abdo799
Why do van de graff generators have a maximum voltage( charge on the sphere ) .
Why can't they just accumulate charge on the sphere as large as we desire?

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"The maximum achievable potential is approximately equal to the sphere's radius multiplied by the e-field where corona discharges begin to form within the surrounding gas. For example, a polished spherical electrode 30 cm in diameter immersed in air at STP (which has a breakdown voltage of about 30 kV/cm) could be expected to develop a maximum voltage of about 450 kV."
http://en.wikipedia.org/wiki/Van_de_Graaff_generator

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## 1. What is a Van de Graaff generator?

A Van de Graaff generator is a device used to generate high voltages, typically in the range of thousands to millions of volts. It consists of a large metal sphere or dome connected to a moving belt, which accumulates electric charge and transfers it to the sphere, creating a high voltage potential difference.

## 2. What is the maximum voltage that a Van de Graaff generator can produce?

The maximum voltage that a Van de Graaff generator can produce depends on various factors such as the size and shape of the generator, the type of material used for the belt, and the environmental conditions. However, most commercial Van de Graaff generators can produce voltages up to 5-8 million volts.

## 3. How does a Van de Graaff generator produce such high voltages?

A Van de Graaff generator uses the principle of electrostatic induction to produce high voltages. As the belt moves, it rubs against a comb-like structure called a collector, which accumulates electric charge. This charge is then transferred to the metal sphere, creating a high voltage potential difference between the sphere and the ground.

## 4. What are the practical applications of Van de Graaff generators?

Van de Graaff generators have various practical applications such as in nuclear physics research, particle accelerators, and as a source of high voltage for experiments and demonstrations. They are also used in electrostatic paint spraying, air pollution control, and in medical devices such as X-ray machines.

## 5. Are there any safety concerns when using a Van de Graaff generator?

Yes, there are several safety concerns when using a Van de Graaff generator. The high voltages produced can be dangerous and can cause electric shock. It is important to follow proper safety precautions and use insulating materials when working with a Van de Graaff generator. It is also important to ensure that the generator is grounded to prevent the buildup of static electricity.

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