History of Electricity: <ul><li> ATOMS </li></ul><ul><ul><li>Law of charges </li></ul></ul>
History of Electricity: <ul><li>The Greeks were the first to discover electricity about 2500 years ago. They noticed that when an amber was rubbed with other materials it became charged with an unknown force that had the power to attract objects such as dried leaves, feathers, bits of cloth, or other lightweight materials. The Greeks called amber electron. The word electric was derived from it and meant "to be like amber," or to have the ability to attract other objects. </li></ul>
ATOMS <ul><li>The atom is the basic building block of the universe. All mater is made from a combination of atoms. Matter is any substance has mass and occupies space. Matter can exist in any of the three states: solid, liquid, or gas. Water, for example, can exist in the form of ice, as a liquid, or as a gas in the form of steam. An element is a substance that cannot be chemically divided into a simpler substance. An atom is the smallest part of an element. The three principle parts of an atom are the electron, neutron, and the proton. It is theorized that protons and neutrons are actually made of the smaller particles quarks. </li></ul><ul><li>The proton has a positive charge, the electron has a negative charge, and the neutron has no charge. The Neutron and proton combine to form the nucleus of the atom. Since the neutron has no charge, the nucleus will have a net positive charge. The number of protons in the nucleus determines what kind of element an atom is. Oxygen, for example, contains 8 protons in its nucleus, and gold contain 79. The atomic number of an element is the same as the number of protons in the nucleus. The lines of force produced by the positive charge of the proton extend outward in all directions. The nucleus may or may not contain as many neutrons as protons. For example, an atom of helium contains two protons and two neutrons in its nucleus, while an atom of copper contains 29 protons and 35 neutrons. </li></ul>
Law of charges: <ul><li>The law of charges states that opposite charges attract and like charges repel. For example, two objects that contain opposite charge are attracted to each other. The two positively charged objects and two negatively charged units repel each other. The reason for this is that lines of force can never cross each other. The outward-going lines of force of a positively charged object combine with the inward-going lines of force of a negatively charged object. This combining produces an attraction between the two objects. If the two objects with like charges come close to each other, the lines of force repel. Since the nucleus has a net positive charge and the electron has a negative charge, the electron is attracted to the nucleus. </li></ul><ul><li>Because the nucleus of an atom is formed from the combination of protons and neutrons, one might ask why the protons of the nucleus do not repel each other since they all have the same charge. Two theories attempt to explain this. The first asserts that the force of gravity holds the protons and neutron together. Neutrons, like protons, are extremely massive particles. Their combined mass produces, the gravitational force necessary to overcome the repelling force of the positive charges. The second explanation involves a theoretical particle called gluon. A gluon is a subatomic particle that acts as a bonding agent that not only holds quarks together, but also holds the protons and neutrons together. </li></ul>
Why is Basic Electrical Safety Important? <ul><li>Simply put, electricity is dangerous. As such, anyone working with or near electricity should be educated on how to properly prevent basic electrical safety hazards. Unfortunately, this wonderful thing we call electricity can be conducted by human bodies. With greater misfortune still is that when electricity runs through a human body, it can cause severe damage, unlike metals, which upon conduction remain basically unaffected. When a human body conducts electricity, the experience can range from painful shock to fatality. Surprisingly, relatively small currents can have dramatic effects. It is important to understand the difference between voltage and current. A basic analogy for voltage is that it is the electrical equivalent of water pressure. Amperage is like flow of water. A relatively small flow of electricity (amps) at a standard voltage can cause a painful shock. For example, the amount of power that flows into a laptop can be enough. </li></ul>
IMPORTANCE OF ELECTRICAL SAFETY <ul><li>Electrical Safety is important, but by no means the end of the road when it comes to adequate protection against electrical hazards. This article on basic electrical safety will by no means make you sufficiently prepared for tasks involving work with or around electricity. Rather, this basic electrical safety discussion will give you a foundation on which to build your knowledge to best protect against the dangers of electrical hazards. </li></ul>
<ul><li>*Never use electrical tools on damp ground or around water </li></ul><ul><li>*Never place an antenna near power lines </li></ul><ul><li>*Keep a safe distance from pad mounted transformers. </li></ul><ul><li>*Never insert anything (especially metal) into an electrical appliance (such as a toaster) </li></ul><ul><li>*Do not overload electrical outlets with too many electrical plugs. Buy one surge protector with many outlets instead of ‘daisy-chaining’ smaller power splitters </li></ul><ul><li>*Wear rubber gloves and rubber boots when working near electrical components. </li></ul><ul><li>*Inspect tools and appliances for wear and damage prior to use </li></ul><ul><li>*Use electrical tape for power cord management, do not use staples </li></ul><ul><li>*Always use the correct size fuse, never use a fuse with a larger amperage allowance than the original </li></ul><ul><li>*When working near power lines, use ladders made of wood instead of metal </li></ul><ul><li>*If you have a bad feeling about some work concerning electricity, stay away! </li></ul><ul><li>*Know where breakers and electrical boxes are in case of an emergency </li></ul><ul><li>*Label circuit breakers clearly </li></ul><ul><li>*Do not use electrical outlets or cords with exposed wiring </li></ul><ul><li>*Do not touch a person or electrical apparatus in the event of an electrical accident. Always disconnect the current first. </li></ul><ul><li>*Do not clean tools with flammable or toxic solvents. </li></ul>
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