to prevent dust and soot particles from polluting the atmosphere, industry often employs static electric charge in their smokestacks. explain the physics principle involved in this application

The physics principle involved in employing static electric charge to prevent dust and soot particles from polluting the atmosphere is known as electrostatic precipitation.

Electrostatic precipitation takes advantage of the principle that opposite charges attract each other. The process involves three main components: a corona wire, collecting electrodes, and a power supply.

First, a corona wire is placed at the center of the smokestack. This wire is connected to a high voltage power supply, which creates a strong electric field around the wire. When the power supply is turned on, it charges the corona wire with a high voltage.

As the dirty gases containing dust and soot particles flow through the smokestack, they pass by the negatively charged corona wire. Due to the strong electric field, electrons are stripped from air molecules near the wire, creating negatively charged ions.

These charged ions then migrate toward the positively charged collecting electrodes, which are usually placed at the sides of the smokestack. As the dirty gases flow through the smokestack, the charged particles are attracted toward the collecting electrodes.

The collecting electrodes, which typically have a large surface area and are made of metal, act as grounded plates. As the charged particles approach these collecting electrodes, they are neutralized by gaining or losing electrons, forming solid particles.

These solid particles, now neutralized, lose their ability to be suspended in the gas stream and instead settle on the collecting electrodes or fall down as ash. Eventually, these collected particles can be removed from the collecting electrodes through cleaning methods or disposed of properly.

By using electrostatic precipitation, industry can effectively remove dust and soot particles from the air before they are released into the atmosphere, reducing pollution and improving air quality.