Like poles repel, unlike poles attract. This is probably one of the most expensive phrases in the English language. Let me explain to you why. This phrase has what has led to the development of electric current. Electricity is used in everyday life. In this article, we will explain how electricity works and how various electrical appliances use electricity in our homes.
To fully understand electricity, we have to begin with matter. Matter is anything that has mass and can occupy space. This definition groups matter into solids, liquids and gases. Hence, everything we know is matter because it has mass(weight) and can fill a space(volume).
Atoms are the smallest particle of matter that can form a chemical element. Everything in the universe is made up of atoms since an atom is the smallest particle of matter (check the definition above). This implies that every substance is made up of atoms.
The structure of an atom
Atoms have a central structure called the nucleus. Inside the nucleus are protons and neutrons. Protons have a positive charge and neutrons have no charge at all, i.e., neutral. Around the nucleus are electrons that are negatively charged. The number of neutrons, protons and electrons an atom has can inform us about the type of material. For instance, copper(which is a metal) has 29 protons, 34 neutrons and 29 electrons. Whilst the neutrons and protons are fixed in the nucleus, the electrons which are negatively charged circulate around the nucleus in a constant motion. The electrons are lighter in mass so they move quickly like the speed of light. Due to this behaviour, an atom will lose or gain electrons easily.
As mentioned earlier, the atoms are found in shells around the nucleus. Each shell can take a specific number of electrons depending on the type of atom. The first shell contains 2 electrons, the second shell contains 8 electrons, the third shell contains 18 electrons and so on. The electrons in the outer shell determine whether an atom will be stable or not. Electrons that move around the outer shell are free and can move from one atom (matter/substance) to another.
Conductors and Insulators
As mentioned earlier, the free electrons are determined by the type of atom. There are usually two main types of materials- a conductor and an insulator. A conductor allows the free electrons to move freely, examples include metals such as copper, iron, gold, etc.
An insulator, on the other hand, prevents the electrons from moving freely. Examples include glass, wood, plastic.
Generally, an atom will have an equal number of positive charges (protons) and negative charges (electrons) whether it is a conductor or an insulator. However, that can change when the electrons in the outer shell of the atom lose or gain. Fortunately, the electrons in an insulator are limited so nothing of that sort can happen. The focus now shifts to conductors since they can either gain or lose electrons.
For instance, if an atom gains electrons, the number of electrons increases and it becomes negatively charged. On the other hand, if it loses the free electrons in the outer shell to another atom (conductor), it becomes positively charged because the protons in the nucleus supersede the electrons in the outer shell. A charged atom is either a positive or a negative ion. When you rub your feet against another object, for example, a carpet- you force electrons to move from the carpet to your body. Your body becomes negatively charged. As you touch a conductor or a metallic surface like a doorknob, the electrons move from your body to the doorknob restoring your body to a zero charge. This always happens in nature.
Note that, the electrons always move from either a positive ion to a negative ion. Like poles which are electrons will always repel but when a positive atom comes into contact with a negative atom, electrons will flow. It is out of this phenomenon that electricity was coined. The electrons in atoms gives produces an electric charge.
Electricity is simply the flow of electric charges. Electricity makes use of the charged particles -electric charge through conductors like copper wire which sends electrical current from a power source to something that we wish to power. The electrons do not travel along the wire, the atoms in the wire bang into each other, transferring the electrons (electrical charge) from a positive atom to the negative atom. To create a complete circuit, an electrical appliance is fixed in between the positive ion and the negative ion. Electric current then flows from the positive ion through the electrical appliance to the negative ion creating electricity in our homes.
Electricity can only work when the electrical appliance in our home is switched on. When the switch is off, it means that the circuit is closed. A circuit is a closed path that allows the electricity to flow from the positive end through to the negative end.
For electricity to flow through your electrical appliance like e television, you need something to push the electrons from one side to another. That something is called an electromotive force (EMF). A power outlet or battery creates the electromotive force that makes the electrons flow. This electromotive force is commonly known as voltage.
Electricity will flow in your home appliance only when the circuit is closed. When the circuit is closed, it means that you have turned on your electrical appliance so the current can flow from one end to another.
Hence, this happens when you turn on your electrical appliance. To prevent the flow of electricity, always turn off the switch of your electrical appliance when not in use.
- How is electricity made? Retrieved from https://justenergy.com/learning-center/electricity/
- Electricity. Retrieved from https://www.explainthatstuff.com/electricity.html
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