Friday, December 11, 2009

Why do people get shocked?
Electricity flows through water almost as easily as it travels through the wire that brings electricity to your house.
Your body is 70% water. So if you touch electricity, it will flow through you, and you will be badly hurt.
The amperage of the electric current and length of time you're in contact with it, determines the injury.
Be Safe Around Electricity!
Avoid Electric Shock!
Never climb utility poles or play on fences around substations.
Keep electrical cords and wires away from heat and water.
If you are touching water, never touch electrical devices such as light switches, hair dryers curling irons, mixers, or toasters.
Don't pull on electric cords to unplug them.
Keep kites away from power lines, and never fly metallic balloons outside.
Don't put your fingers in a light bulb socket.
If you see a fallen electrical wire, stay away!
Disconnect appliances before cleaning them.
Tell someone if you see a frayed cord.
Don't swim during an electrical storm.
Don't touch overhead wires when you're carrying a ladder, pool skimmer, or any other long object.
Don't climb a tree that has power lines running through or near it.
Don't use an electrical appliance when you're wet.

Wednesday, December 9, 2009

How can electricity harm us

Contact with electricity can cause:

Electrical shock
this is when electrical current passes through the body. Even a small shock can be frightening and painful.
Burns
electrical current can burn the skin, nerves, muscles and tissues in the body.
Death
a severe electrical shock can cause problems with a person's breathing and heartbeat, possibly leading to death.
What to do in an electrical emergency
Downed Wire

Stay away from all downed wires - even if there are no sparks.
Do not touch anything, or anyone, that is touching an electrical wire.
Get help right away.
Downed Wire Touching a Vehicle
If you are inside a vehicle, wait inside for help.
If you must get out, jump clear without touching the ground and the vehicle at the same time.
If you are a witness, stay clear and call for help.
Electrical Fire
Get help right away.
Unplug the faulty appliance to turn off the power, if possible.
Important: Never throw water on an electrical fire.
Electrical Shock
Never touch a person who is being shocked.
Unplug the faulty appliance or turn off the power, if possible
Call for help immediately.

Electric Vehicles

Electric Vehicles (EVs) run on electrical energy instead of gasoline or diesel fuel. Thousands of EVs are on the road today. They are popular for many reasons:
EVs help reduce pollution.
EVs cost less to run than gasoline vehicles.
EVs reduce our dependency on gasoline.
EVs do not need motor oil or antifreeze and do not need belts, hoses, filters, and pumps.
How EVs Work
Like gasoline tanks, batteries store the fuel used to operate an EV. EV batteries can be charged by plugging the vehicle into a charging station. The batteries store the electricity until the vehicle is driven.Under the hood, an EV consists of an electric motor, one or more controllers, and batteries. The controller governs the amount of electricity that flows from the batteries to the motor when the driver steps on the accelerator. The motor changes electrical energy from the batteries to mechanical energy, which makes the vehicle move.
EVs and the Environment
Gasoline-fueled and diesel-fueled vehicles produce about half of the pollution in U.S. cities. Electric vehicles offer a non-polluting alternative. Even when pollution related to power plant electricity production is factored in, EVs generate less air pollution than gasoline- and diesel-fueled vehicles.
For every mile travelled in an EV instead of a gasoline vehicle, the following pollutants are reduced:
Carbon monoxide, nitrogen oxide, and volatile organic compounds, all of which are key ingredients in smog.
Carbon dioxide, which is not an air pollutant but may contribute to the possible risk of global warming.

Pioneers of elecricity

Alexander Graham Bell (1847-1922)
Alexander Graham Bell invented the telephone. In 1876, he spoke the first sentence over it: “Watson, come here, I want you.” The telephone was exhibited at the 1876 Centennial Exposition in Philadelphia, Pennsylvania.
Thomas Alva Edison (1847-1931)

Thomas Alva Edison invented the phonograph, the motion picture camera, and more than 1,000 other things. Edison is best known for inventing the incandescent lightbulb in 1879. Prior to the incandescent bulb, the world relied on oil lamps and natural gas to light the night. Edison’s bulb consisted of carbonized cotton filament housed in a vacuum inside a glass bulb. The current flowing through the filament would cause it to radiate a steady glow. The vacuum was needed to keep the filament from burning up.While still working on the lightbulb, Edison began thinking about an electric system that would provide electricity from a central power station and deliver it to homes and businesses. He designed the country’s first central power system, which began operating in New York City in 1882 and provided service to 85 customers. By 1902, only 20 years after the New York system began operations, there were 3,500 different electric systems in the U.S. alone. Thanks to Edison, the world was given not only the incandescent lightbulb, but also efficient systems to supply electricity to people.
Michael Faraday (1791-1867)
Michael Faraday invented the generator in 1831. Before then, all useful electricity was supplied by batteries. Faraday’s generator provided a source of current that did not depend on batteries.
Benjamin Franklin (1706-1790)
Contrary to popular opinion, Benjamin Franklin probably did not tie a key to a kite and fly it in a lightning storm. Franklin did, however, perform many experiments to learn more about electricity. One year Ben Franklin wanted to use electricity to kill a turkey for Christmas dinner. While checking his equipment, he touched two parts at the same time and got a big shock. His whole body vibrated, and his arms were numb until the next morning. He was lucky he wasn’t burned or electrocuted! Franklin believed that lightning was a flow of electricity taking place in nature. He knew the dangers and probably did not want to risk electrical shock by flying a kite in a storm. In 1752, Benjamin Franklin’s electricity experiments led him to invent the lightning rod, which when placed at the top of a barn, church steeple, or other structure, conducts lightning bolts harmlessly into the ground.
Lewis Howard Latimer (1848-1928)
Lewis Howard Latimer was a pioneer in the development of the electric lightbulb. He was the son of a former slave, and was the only African American member of Thomas Edison’s research team of noted scientists. While Edison invented the incandescent bulb, it was Latimer who developed and patented the process for manufacturing the carbon filaments within the bulb.
Granville Woods (1856-1910)
Granville Woods had prolific inventive skills and made ingenious contributions to mass transit. Woods patented a telephone transmitter in 1885, which was bought by Bell Telephone. He then founded the Woods Electric Company in New York City, which manufactured and sold telephone, telegraph, and electrical instruments. His most important invention was the induction telegraph system in 1887, a method of informing an engineer of trains immediately in front of and behind him, thus ensuring safer rail travel. Of the more than 60 patents that Woods registered, the majority were concerned with railroad telegraphs, electrical brakes, and electrical railway systems.

Wednesday, December 2, 2009

Electricity is the wonder of science without which we can't exist in todays scenario. We are using electrical devices in almost all spheres of our life.

Friday, November 27, 2009

Electronics with Rinku

Hello

I am Rinku Bidani working as a teacher in Kulachi Hansraj School, Delhi. My subjects are electronics and science.