2 devices that use static electricity to funtion
1. Van de Graaff generator
When the motor is turned on, the lower roller (charger) begins turning the belt. The belt is made of rubber and the lower roller is covered in silicon tape, the lower roller begins to build a negative charge and the belt builds a positive charge. Silicon is more negative than rubber so the lower roller is receiving electrons from the belt when it goes over the roller.
The positively charged atomic nuclei, try to move toward the negatively charged roller, but the belt is in the way. So now the belt gets "coated" with the positive charge, which it then carries away from the roller.
The belt is positively charged and rolling toward the upper roller and upper brush assembly. Since the upper roller is nylon, it wants to repel the charge on the belt. The electrons in the brush move to the tips of the wires because they are attracted to the positively charged belt. Once the air breaks down as before, the positive atomic nuclei of air are attracted to the brush. At the same time, the free electrons in the air move to the belt. When a charged object touches the inside of a metal container, the container will take all of the charge, leaving the object neutral. The excess charge then shows up on the outside surface of the container. The container is the sphere. For the Van de Graaff generator, the belt is the charged object, delivering a continuous positive charge to the sphere.
2. Laser Printer
The core component of this system is the photoreceptor, typically a revolving drum or cylinder. The drum is positively charged by the charge corona wire, a wire with an electrical current running through it. As the drum revolves, the printer shines a tiny laser beam across the surface to discharge certain points. In this way, the laser "draws" the letters and images to be printed as a pattern of electrical charges an electrostatic image. The system...
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