Van De Graff Generators

1. User turns crank
2. User brings handle to the globe
3. Electrostatic Bang!

• Cranks connects to a white roller, and next to it some metal teeth
• Roller connnects to transparent belt, and on the other end, under the globe, there is a similar roller
• Metal combs next to rollers
• When cranks are turned, the bottom roller becomes negative, and the top roller becomes positive
• So, electron flow between handle (connected to bottom) and globe (connected to top)

Van de graff generator so exciting because, unlike normal statics, charges are added from the inside (see, wire B from the figure)

• When you add additional changes, because conductor wants to stay 0, the additional charges can't do anything but accept it
• Sphere slightly curved to make up for gaping hole
• Normal door-handle statics would much rater simply eject the added change as their electric field is pointed at one direction against charge introduction

• One dome that's positive, one dome is negative
• So, what happens when Spark! happens?
  • Enough charge to overcome the electric field resistance KBhPHYS201ResistanceConductivity of air (like 3.4 million Volts/metre), and air ionizes — air atoms becomes so attracted that their electrons ditch their nuclei and air suddenly becomes a conductors
  • Neutral air has high resistance, but when it ionizes, the air looses its resistance (drops) and becomes nicely conductive
  • So then, current (Coulomb/s) that flow in the air suddenly spark up because of sudden loss of resistance, discharging the negative dom