Static Electricity – Static electricity is electricity with a charge in a stationary or static state, in contrast to dynamic electricity whose electric charge is always moving. In meaning, static electricity is an imbalance of electric charge in or on the surface of an object. Meanwhile, the electric charge remains until it is dissipated by being removed.
Electricity comes from the Greek word electron which means amber. Amber itself is a petrified resin tree. This property of stone attracts small objects after rubbing, which was later developed by a Greek scientist named Thales of Miletus with experiments that resulted in the discovery of an electric charge.
Definition of Static Electricity
What is meant by static electricity? In general, static electricity is a collection of electric charges in a fixed amount or the balance of electric charges in an object. Just like when you rub a plastic ruler through your hair, the ruler will be negatively charged, while the hair will be positively charged.
The discharge when these two materials are rubbed makes them electrified with a negative charge. Electric charge is a physical quantity related to electrical and other related effects in matter. Charges can be neutralized by means of friction indicating that charges do not cancel each other’s effect.
The amount of electric charge will depend on the deficiency or excess of the number of electrons, the more excess and deficiency of electrons an object has, the greater the electric charge. According to the electron theory, electrons that move from one atom to another are called free electrons, while objects that can move free electrons are called conductors.
A static electric charge is created whenever two surfaces are connected and separated, and at least one of the surfaces has a high resistance to electric current (and is therefore an electrical insulator). The effect of static electricity is familiar to most people because people can feel, hear, and even see the spark as an excess charge is neutralized when brought close to a large electrical conductor (eg grounded).
The coulomb is a unit for measuring the size of an electric charge. There are positive and negative electric charges. An excess of electrons in an object causes the object to have a negative electric charge, and if the object is positively charged then the object is deficient in electrons. The number of negative and positive charges on an object is the same, so the object has a neutral charge. 1 Electron = -1.6 x 10-19 coulomb 1 Proton = -1.6 x 10-19 coulomb.
Static Electricity Concept
As reported by the Britannica.com page , the notion of static electricity is an electrical phenomenon that occurs when charged particles are transferred from one object to another. This transfer of charge occurs because of the two objects rubbing against each other. Like dust flying with the air rubbing against the surface of the TV screen. From this friction, there is a transfer of electron charge.
Now, when the electron charge moves, both objects can experience an excess of electrons so that they are negatively charged. It also lacks electrons so it is positively charged. Because there is a difference in the nature of this charge, the two objects end up attracting each other.
Well, that’s the concept of static electricity, so what’s the difference with dynamic electricity? The difference between static and dynamic electricity is that static electricity tends to be still or does not move, while dynamic electricity can move or flow.
What does it mean? Okay, let’s do an experiment, shall we? Now take a plastic ruler and rub it through your hair. When a plastic ruler is rubbed against the hair, there will be a transfer of electrons from the hair to the ruler, so that the plastic ruler becomes electrically charged. Well, the electric charge on this ruler will not flow so it is called static electricity.
Now try to bring the ruler closer to the small pieces of paper. What happened? The piece of paper will stick to the plastic ruler due to the transfer of electric charge. However, this only lasted temporarily. After the electric charge on the plastic ruler and the piece of paper is the same, the two objects will repel each other. As a result, the pieces of paper will come off the ruler.
So, what about dynamic electricity? In dynamic electricity there is a flow of electric charge. For example, when you press the switch in the ON position, there will be an electric current that causes the light to turn on. However, when you press the switch in the OFF position, the light will turn off because the electricity has stopped.
Okay, let’s continue to the discussion about electric charge, come on. In essence, in static electricity we talk about an object or atom that has an electric charge. Therefore, we should first get acquainted with the name of the atom. You must have often heard of atoms? First of all, try to observe the atomic image below.
As you can see in the picture of the atom above, the atom consists of two parts, namely the atomic nucleus and the atomic shell. The atomic nucleus is composed of two kinds of particles, namely protons (positively charged) and neutrons (no charge/neutral). Meanwhile, the atomic shell is composed of negatively charged particles called electrons.
So, why are there objects that are negatively charged and some are positively charged? Well, basically the atom is neutral charge. However, the atom will turn positive or negative if there is a transfer of electrons.
- An atom is said to be neutral if it has the same number of protons and electrons.
- An atom is said to be positively charged if it has more protons than electrons.
- An atom is said to be negatively charged if the number of protons is less than the number of electrons.
Static Electricity Formula
In static electricity, there are several formulas that are usually used. Here is the formula for static electricity that you need to know.
1. Electric Potential
Electric potential is the work per unit charge required to move one charge from one point to another. Well, the magnitude of the electric potential at a point can be calculated by the electric potential formula: