Go with the Flow
                    Think back to your high school classes and all those diagrams of atoms with electrons spinning around the nucleus.  Basically, electrons spin around the nucleus in a circular path.  This is basically because the protons in the atom's nucleus carry a positive charge that attracts the electrons but the size of the electrons is too small to fit inside the nucleus hence it maintains some gaps.  If enough valance electrons decide to move on preferably in a more or less uniform steam, we end up with usable electricity. The rate of flow of charges or electrons is current.

Current comes in several flavors, but the two most known are,
  • static current: in which the electric charges are stationary 
  • Dynamic current: in which the electric charges are moving in nature.
 Static electricity is simply an imbalance of positive and negative charges.  When you get zapped you're account to trying to balance these charges. To get rid off these static charges anti-static sprays and by touching a metal surface will be a remedy.  Static current may be annoying but dynamic is another level.

When THOMAS ALVA EDISON and his crew invented a reliable electric light bulb, he followed it up by developing power systems to run it, thereby envisioning a future world full of light bulbs.  Edison employed direct current(DC), which now is used as in battery-operated gagets in which the current flows from the negative terminal of the battery to the positive terminal.  A battery is basically a container of chemicals whose electro chemical reactions produce excess electrons.
Our electrical systems use alternating current(AC), which was developed by Edison's contemporary, George westinghouse, after he bought up patents from nikola tesla and william stanley.  Once again, someone with business sense trumped the scientific minds possessing the money-making ideas.  It took edison, a few years to go along with AC.
A direct current just means that the electric current flows continuously one direction and keeps going until it finds something to run such as a load. Whereas in ac as the expansion of it describes of its alternating nature the current in ac circuit reverses alternately with time.

However, AC have some useful consumer friendly features such as

  • Through a series transformers, an AC can be increased or decreased in value. This means that instead of billion watts of power heading for your panel box, you'll get a reduced amount that you actually use.
  • Alternating current is efficiently transported over long-distance power lines.
  • It's easy to convert from ac to dc, but it's expensive to go from dc to ac.
  • power loss is less in ac for long distance transmission than dc.
                   George Westinghouse installed the world's first long-distance AC power lines in the area of San Juan Mountains near Telluride, Colorado.  Rapid expansion of gold mining had exhausted nearby timber supplies, the cheap fuel that ran the  steam-powered machines the mines required.  L.L.nunn, a partner in the mine traveled and convinced Westinghouse to build a generator and a motor in the isolated region. Nunn threw the switch on June 2l, 1891, beginning a new era in electric power in the united states.

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