You’ve probably experienced a static “shock” at least once in your life. That’s an undersell –you’ve probably experienced it at least once this month alone, when you patted your favorite pet, touched a doorknob, or picked up a book. This shock sensation is a perplexing phenomenon, however, given its frequency, it’s often ignored.
Taking phenomenons for granted
It’s easy to take something for granted when we’re constantly surrounded by it. Everywhere we go, everywhere we are, there’s electricity. From powering homes, offices, and factories – electricity is everywhere.
To understand just how electricity has impacted our lives yet how little we know about it, just look at every time there’s a power outage and how people aren’t really familiar with what to do. Basically, we live and breathe through electricity.
This has been the way of life since the 19th century, and we have no plans of going back. It was during the 19th century that pioneers such as Alessandro Volta, Michael Faraday, Joseph Henry, and Thomas Edison figured out the secrets of electricity, how to produce it, and how to make it do useful things.
Background: Questioning the shock
Thales of Miletus might not have been the first person in history to have ever experienced a static shock. However, he was the first one to ever document and study the phenomenon. Thales was a Greek philosopher and mathematician in the sixth century B.C.
The electrical shock experienced during menial tasks is an interesting phenomenon, especially given how it’s experienced infrequently. This poses the question: Is there a way to induce a static shock? Thales might have established a link to some stimuli, nevertheless, it wasn’t until much later that scientists discovered something a lot more convincing than magic – the atom.
Similar to the ancient Greeks, the common everyday man thinks that static electricity is generated by rubbing things together. Our bodies build up a static charge when we walk over carpets or rub our socks across the floor.
Questioning the shock that we regularly experienced and that left us unharmed was quite the turning point. It gave birth to questioning the very existence of a way to harness that shock, or something with a similar capacity to generate energy.
A century later, here we are.
The Atom: The smallest structure in existence
Today, the most accepted understanding of the common static shock is revealed by the discovery of the atom. The smallest whole structure in existence is the atom, which in turn is composed of sub-atomic particles. The atom has a central nucleus composed of protons and neutrons with a surrounding cloud of electrons.
A neuron is neutral, whereas protons and electrons are of opposing charges: positive and negative, respectively. The entire charge of the atom, in its normal state, is neutral. However, an imbalance of electrons would result in either a positive or a negative charge.
Why electrons? Because the sub-atomic particles within the nucleus aren’t capable of losing their positions. Electrons, on the other hand, can freely lose their positions and are transferred from one atom to the other. It’s pivotal to understand at this point that every existing structure; animate or not, is composed of atoms. Whether it’s a human being or a rug, it’s made up of atoms.
Charging up one surface with another
Atoms have clouds of electrons surrounding them in concentric shells. This is a hypothetical concept, however, it’s yet to be proven otherwise. Electrons can freely lose their positions, but there’s a catch. If the concentric shell is that of a noble gas configuration that is similar to the eighth group in the periodic table in their outermost configuration, it won’t readily lose electrons.
Nevertheless, electrons can lose their positions, provided that there is another surface for them to transfer to. A very common example of the classic static shock is when you walk over a fluffy rug with socks.
The atoms within the rug lose their electrons and transfer them to the socks, or vice versa. In either case, both objects lose their normal state and are now charged. In our everyday life, there are numerous objects or likewise people who are unknowingly “charged.”
Let’s say that after acquiring this charge, you remain unaware of its existence until you walk over to your pet. Your pet, in turn, has rubbed himself over the rug a little while ago and has acquired a charge too. You went over to pat your pet and you get a shock.
Unlike charges oppose each other
Whether you’re negatively or positively charged, the fact of the matter is that unless you have an opposing charge nearby, you won’t feel the charge. However, once you come in contact with someone or something of the opposing charge, the two charges will travel towards one another.
Unlike charges attract each other – that’s physics 101. It’s something that has scientists going back and forth.
The triboelectric effect
The simplest way to explain the concept of the electric shock – the static shock – is with the triboelectric effect. This states that all materials are built of atoms with a central core of positive charge with an outer cloud of negative charges. The degree of strength an atom has over its electrons varies from one atom to the other.
When we put two different materials in contact with one another; one attracts electrons more than the other and electrons can be pulled from one to the other. Some materials readily lose their electrons, while some do not.
When you separate these materials, these electrons effectively jump to the material that attracts them more strongly. As a result, one atom has a surplus of electrons and one has a surplus of positive charges. Negative and positive charges on two opposing surfaces – that’s what causes the shock, and that’s the triboelectric effect.
The difference between insulators and conductors
Your electric cables are made up of metal, but the material surrounding them is made up of plastic. These two materials counteract one another. However, they’re both necessary for the overall apparatus to work properly.
Metals are conductors and plastics are insulators. There are a few other items that would be categorized as either one. Conductors can lose their electrons and acquire a positive charge. They conduct the charge onto another.
Insulators, on the other hand, are less prone to losing their charges. Hence, your normal USB wire is made up of conductors and insulators for a dual effect. The conductor loses its charge and transfers charge to your device. The insulator, on the other hand, keeps from that charge reaching you, preventing the static shock.
Everything you’ve just read on static electricity is today’s most accepted theory. However, the thing with science is that it’s ever-changing. Nothing is accepted as a fact unless every other theory contradictory to it fails. The same is the case with static electricity.
In 2011, scientists reported discoveries that suggested new theories and discoveries about static electricity. Rather than being related to a transfer of electrons from one surface to the other as physics would suggest, there’s a hint of underlying chemistry as well.
How? With ions. A simple swap of ions along with some material of the surface is also going on. This research is still new. However, it would unravel a whole other world of static shocks. Rather than losing electrons in itself, you’ll be losing pieces.
What are asperities?
Asperities are imperfections seen at a microscopic level even on smooth surfaces. These tiny bumps and pits are present on every surface: wool, nylon, balloons and anything believed to cause static charge.
When you rub one surface onto another, the asperities scrape together and create friction. Friction is something that has been disputed by scientists. Nevertheless, the existence of asperities reaffirms this theory.
Everyday human activities that generate shock
The most common human activity that can generate shock is by rubbing your feet over a mat. Science has always been up to newer innovations. One such innovation is an anti-static mat. You’d think it’s a static minimizing mat, rather than an anti-static mat in itself. That’s not the case.
Static electricity is the little shock you sometimes experience when you touch an object. Understandably, it comes as a surprise. No one knows whether they’ve been “charged” or not, which is quite perplexing in itself. What causes this charge? Why does it happen with particular stimuli? And, why does it happen at all? These are but a few questions that scientists have been asking themselves for decades.
Today, we attribute this theory to the existence of atoms, asperities and much more. The fact is, however, that it’s a theory still undergoing discovery.