Introduction
Static electricity is a concept we have all come across many times in our lives, from doing simple things in our day to day lives such as walking across the carpet in socks and receiving a shock from a doorknob, or playing as a child and rubbing a balloon on our heads to make our hair stand up.
But why do these things happen? And most importantly, what are the dangers of static electricity?
Who initially discovered the concept of static electricity?
The first signs of the study of static electricity date back to the time of the Ancient Greeks. A philosopher named Thales of Miletus originally noticed the strange behaviors associated with friction between amber and a variety of fabrics which generated an attractive force on objects with static electricity. This exploration dates back to 624 BC.
Subsequently, Italian scientist Niccolo Cabeo began to study the relationship between electricity and magnetism with hopes to improve the accuracy of magnetic compasses. Cabeo studied the research carried out by the British physicist William Gilbert, eventually concluding that there were forces of attraction and repulsion between bodies. This conclusion was formed in the early 17th century.
Lastly, in 1733, the French physicist and chemist Francois de Cisternay du Fay proposed the existence of two different types of charges; positive and negative. Shortly afterwards, in 1785, the French physicist Charles Coulomb also validated the quantitative concepts of electrical forces in a treatise. He developed Coulomb’s Law, which advanced propositions in regards to attraction and repulsion with static electric charges. This law was then enriched by Gauss’s theorem, a theorem which defined almost all electrostatic phenomena.
Static electricity- the basics
Static electricity simply occurs when there is an imbalance of charges, positive and negative, in objects. First, let's begin with the basics.
All matter is made up of atoms, but it is what’s inside of atoms that matters. Atoms are made up of subatomic particles; positively charged protons, neutral neutrons, and negatively charged electrons. Therefore, all things are charged as all things are made up of these subatomic particles.
The phenomenon of static electricity
However, there is usually a balance of charges which makes an object neutral. Objects usually have an equal amount of protons and of electrons. Static electricity requires the separation of positive and negative charges. Occasionally, two surfaces come into contact with one another and electrons migrate from one surface to another, leaving the original surface with an excess of positive charges (the first object is left with more protons than electrons). This surface becomes positively charged, whilst the surface gaining the electrons becomes negatively charged.
The displacement of electrons
The weakly bound electrons gain kinetic energy from the friction between the two surfaces, allowing them to move. Electrons will move to materials with sparsely filled shells, as the materials strive to gain more to fill their outer shells. Electrons will leave their atoms and attach to other atoms.
The triboelectric series
When different materials are rubbed, some of them acquire positive charges while others acquire negative charges. Some materials also acquire more charge than others. It turns out that we can arrange materials in a sort of league table with materials listed from positive to negative according to the charge they gain. The lists vary slightly between books and websites, but they all generally start with minerals (positive), move through neutral items like wood and paper, and end with plastics (negative).
Photo reference- http://soft-matter.seas.harvard.edu/index.php/Triboelectric_series
Static discharge- The spark associated with static electricity
Due to the charge imbalance, or ‘net charge separation’, when newly charged bodies come into contact with another material, the mobile electrons will grasp the first chance they get to go where they are most needed, leaving the negatively charged object to ‘jump onto’ the positively charged one. The excess charges are officially neutralized. The feeling of an electric shock derives from the stimulation of nerves as the neutralizing current flows through your body.
Examples of static electricity
Lightning is a dramatical natural example of static electricity. Though the details seem to be unclear, the initial charge separation is believed to be associated with contact between ice particles and storm clouds
There is also the example of static build-up in flowing flammable and ignitable materials.
The applications of static electricity
Although dangerous, static energy has many applications in the real world.
In power plants that burn fossil fuels, electrostatic precipitators remove smoke from waste gasses before they exit the chimneys.
Precipitators remove irritants, allergens, and harmful particles from a residential HVAC system.
Static electricity is used by inkjet printers and photocopiers to direct a miniscule jet of ink to a particular location on the paper.
Research in nuclear physics uses the Van de Graaff electrostatic generator.
The dangers of static electricity
Dangers of static electricity include:
The movement of electricity through the body can result in everything from a painful zap to falls, burns, or stopping the heart.
The lighting of combustible or explosive materials, which causes flames or explosions.
disruptions in the manufacturing of paper, polymers, composites, liquids, powders, and other materials.
Electrical components and gadgets may be harmed by electrostatic discharge (ESD).
Mechanical components like bearings can be damaged by sparking through the oil coats on their surfaces.
Conclusion
When several components of the triboelectric series rub against one another, electric charges accumulate and result in static electricity. When rubbed against materials lower in the series, materials higher in the series rapidly lose electrons.
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