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Electrostatic Generators

By : Shady Ahmed Abd al-ghaffar Sec(5)

2 Electrostatic Generator: is a device that produce static electricity at high Voltage and low Current.

This static Electricity is generated by Friction or Induction.

It is used to demonstrate electrical forces and high voltage phenomena.

3 Examples:-

Van de graaff generator.

Wimshurst machine.

4 Van de graaff generatorPrinciple of Generator: Generally generators works on the

principle of faraday’s law. but, our Van De Graaff Generator works on the static electricity concept.

This generator doesn’t have field winding and conductor.

5 Construction of The Generator: Major parts of Generator are:MotorTwo rollersA beltTwo brushes An output terminal(usually a aluminum sphere).

6 Working of Generator: A small motor causes the rollers To spin. The Rubber belt becomes positively Charged at the bottom and moves upward. When the positively charged belt Reaches the top it gains electrons And make the metal sphere positive.

7 Working of Generator:

The belt goes back down to The bottom and loses its electrons To become positive again.

The potential difference achieved in modern Van de Graaff generators can reach 5MV.

8 Applications

It is used to generate x-rays, which is widely used in medicine field.

It is used in atom smasher’s, which is used in research purposes.

It found applications in physics, medicine, and astro physics.

9 Wimshurst machine Electrical device that can produces a high Voltage by building up charge of static electricity.

It causes very good results to power X-ray tubes.

10 Construction

11 As one or both of the wheels spin, static electricity is generated.

The charge collectors conduct this Charge into the insulators where it is stored.

12 One Layden jar will become negativly charged and the other will become positively charged.

13 Eventually the insulators will have stored enough charge to Send spark across the metal balls.

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Thank you.