The document describes two types of electrostatic generators: the Wimshurst machine and the Van de Graaf generator. The Wimshurst machine uses two plastic discs to generate static electricity through friction, storing the charges in Leyden jars. The Van de Graaf generator uses a motor-powered rubber belt to induce charges on a hollow metal sphere, creating high voltage static electricity. Both devices produce sparks through the separation of positive and negative charges.

1. Electrostatic Generators

2. Electrostatic Generators
A device that produces static electricity at high
voltage and low current.
This static electricity is generated by friction or
induction.

3. Wimshurst Machine
Charge Collector
2 Plastic Discs
Metal Ball (site of
discharge)
Layden jars (store
electric charge)
Rotator Wheel
Base

4. Wimshurst Machine
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.

5. Wimshurst Machine
One Leyden jar will become negatively charged
and the other will become positively charged.

6. Wimshurst Machine
Eventually the insulators will have stored enough
charge to send a spark across the metal balls.

7. Van der Graaf Generator

8. Van der Graaf Generator
1) hollow metal sphere
2) upper electrode (passes
on charges)
3) upper roller (conductor)
4) side of the rubber belt
with positive charges
5) opposite side of the
belt with negative charges

9. Van der Graaf Generator
6) lower roller (insulator)
7) lower electrode (ground)
8) spherical device with
negative charges, used to
discharge the main sphere
9) spark produced by the
difference of potentials

10. Van der Graaf Generator
A small motor causes the
rollers to spin.
The rubber belt becomes
positively charged at the
bottom and moves upward.

11. Van der Graaf Generator
When the positively
charged belt reaches the
top it gains electrons and
makes the metal sphere
positive.

12. Van der Graaf Generator
The belt goes back down to
the bottom and loses its
electrons to become
positive again.