What is Electricity?

Electricity is a basic part of nature and it is one of our most widely used forms of energy. We get electricity, which is a secondary energy source, from the conversion of other sources of energy, like coal, natural gas, oil, nuclear power and other natural sources, which are called primary sources. Many cities and towns were built alongside waterfalls (a primary source of mechanical energy) that turned water wheels to perform work. Before electricity generation began slightly over 100 years ago, houses were lit with kerosene lamps, food was cooled in iceboxes, and rooms were warmed by wood-burning or coal-burning stoves. Beginning with Benjamin Franklin's experiment with a kite one stormy night in Philadelphia, the principles of electricity gradually became understood. Thomas Edison helped change everyone's life -- he perfected his invention -- the electric light bulb. Prior to 1879, direct current (DC) electricity had been used in arc lights for outdoor lighting. In the late-1800s, Nikola Tesla pioneered the generation, transmission, and use of alternating current (AC) electricity, which can be transmitted over much greater distances than direct current. Tesla's inventions used electricity to bring indoor lighting to our homes and to power industrial machines. Electricity is used everywhere, from homes to Hospitals. Any appliance in our home connected to the plug is using

  • Word count: 1149
  • Level: GCSE
  • Subject: Science
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What effects the resistance of a piece of wire?

What effects the resistance of a piece of wire? I have been asked to find out what will effect the resistance of a piece of wire. There are a few variables that I could test: * The thickness of a piece of wire * The type of wire * The length of the wire * The temperature The variable I have chosen to use is the length of the wire. I predict that the resistance will be higher when the wire is longer, therefore if I doubled the length of the wire the resistance would also double. I predicted this because if the wire is doubled there would be twice as many ions and electrons in the wire, and when the power in the wire is switched on the ions and electrons collide with each other and release heat energy, which is the resistance. So, if I doubled the length of the wire from 4cm to 8cm there would be twice as many ions and electrons in the 8cm piece of wire than in the 4cm piece of wire meaning there would be twice as many collisions making twice as much resistance. So the resistance of an 8cm piece of wire is double the amount of a 4cm piece of wire. Here is a diagram to show this: To carry out my experiment I will need: * An ammeter measured to the nearest 0.2A * A variable resistor * A voltmeter * 100cm of Nichrome wire * A powerpack * Crocodile holders for the wire Here is a diagram of how I will set up my experiment: As a safety precaution for this

  • Word count: 944
  • Level: GCSE
  • Subject: Science
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Wind Power.

Wind Power The wind turbine, also called a windmill, is a means of harnessing the kinetic energy of the wind and converting it into electrical energy. This is accomplished by turning blades called aerofoils, which drive a shaft, which drive a motor (turbine) and ar e connected to a generator. "It is estimated that the total power capacity of winds surrounding the earth is x 1011 Gigawatts" (Cheremisinoff 6). The total energy of the winds fluctuates from year to year. Windmill expert Richard Hills said that the wind really is a fickle source of power, with wind speeds to low or inconsistent for the windmill to be of practical use. However, that hasn't stopped windmill engineers from trying. Today, there are many kinds of windmills, some of which serve differen t functions. They are a complex alternative energy source. What to consider when building a windmill In choosing where to build a windmill, there are many important factors to consider. First is the location: 1) Available wind energy is usually higher near the seacoast or coasts of very large lakes and offshore islands. 2) Available wind energy is gene rally high in the central plains region of the U.S. because of the wide expanses of level (low surface roughness) terrain. 3) Available wind energy is generally low throughout the Southeastern U.S. except for certain hills in the Appalachian and Blue Rid

  • Word count: 4361
  • Level: GCSE
  • Subject: Science
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