how does electricity works

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How does Electricity work?

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Page 1: How does electricity works

How does Electricity work?

Page 2: How does electricity works

To understand electricity well we must possess the knowledge of matter first.

Page 3: How does electricity works

Matter is anything that occupies space and has weight.

Matter may either consist of various elements or occur as a single element.

An element is a substance which cannot be split into simpler substances. For example copper, oxygen, carbon, gold etc.

Elements are made up of many atoms. An atom is the smallest electrically neutral

indivisible particle of an element which takes part in a chemical reaction.

Page 4: How does electricity works

Atoms are made up of Protons, Neutrons and electrons. Each of these has at least one property: Protons are positively charged Electrons are negatively charged Neutrons have no charge

Page 5: How does electricity works

The visualised structure of an atomIt’s a Carbon - 12 atom

Energy shell

Page 6: How does electricity works

Now that we have acquired the knowledge of matter, let’s get back to Electricity.

Page 7: How does electricity works

Electricity is a branch of science concerned with charges.

Page 8: How does electricity works

Dry cells Solar cells

Electricity is often drawn from these devices:

Page 9: How does electricity works

Acid batteryDynamos (a.c and d.c)

Page 10: How does electricity works

In Electricity, we have terms like Conductors and Insulators

Page 11: How does electricity works

Conductors are materials/substances that allow electricity to pass through them easily. Examples are; copper, aluminium, silver and all wet substances. Copper and silver are good compared to other conductors because they have very low resistance.

Page 12: How does electricity works

Insulators are materials that do not allow electricity to pass through them easily. Examples are; papers, rubber, dry wood, plastics, glass, polyvinyl chloride and Bakelite. Rubber and glass are good insulators compared to others because they have very high resistance.

Page 13: How does electricity works

There are two types of electricity:1. Static electricity2. Current electricity

Page 14: How does electricity works

Static Electricity is where both positive and negative charges do not move in a material. Either of the charges gather on a surface of a material without moving.

Whereas Current Electricity is where electrons move freely in a conductor.

Page 15: How does electricity works

Probably you have heard of these terms:

Electric Current, this is the drift of electrons in a conductor. (The electrons move from atom to atom in the conductor). It is also the charge flowing in the circuit per unit time.Electric Circuit, this is the path of electricity or conductors along which electricity flows.

Page 16: How does electricity works

Ampere. An ampere is the SI unit of Current often abbreviated as A.When an electric current flows through a wire a potential difference is said to exist.

A Potential difference between two points A and B (in a circuit) is the work done when moving a unit of charge from A to B.Volt is the SI unit of Potential difference.

When current flows through a circuit, some components in the circuit pose opposition against it. This opposition is called Resistance.The SI unit of Resistance is ohm, its symbol is Ω.