Basic facts about electricity
Electric power is the rate at which electrical energy is transferred by an electric circuit. The SI unit of power is the watt, one joule per second.
Electric power is usually produced by electric generators, but can also be supplied by sources such as electric batteries. It is usually supplied to businesses and homes by the electric power industry through an electric power grid. Electric power is usually sold by the kilowatt hour (3.6 MJ) which is the product of power in kilowatts multiplied by running time in hours. Electric utilities measure power using an electricity meter, which keeps a running total of the electric energy delivered to a customer.
Electrical power provides a low entropy form of energy and can be converted into motion or other forms of energy with high efficiency.
Electric power, like mechanical power, is the rate of doing work, measured in watts, and represented by the letter P. The term wattage is used colloquially to mean "electric power in watts." The electric power in watts produced by an electric current I consisting of a charge of Q coulombs every t seconds passing through an electric potential (voltage) difference of V is
P = \textwork done per unit time = \frac VQt = VI \,
Q is electric charge in coulombs
t is time in seconds
I is electric current in amperes
V is electric potential or voltage in volts
An electrician is a tradesperson specializing in electrical wiring of buildings, stationary machines. and related equipment. Electricians may be employed in the installation of new electrical components or the maintenance and repair of existing electrical infrastructure. Electricians may also specialize in wiring ships, airplanes, and other mobile platforms, as well as data and cable.
Many jurisdictions have regulatory restrictions concerning electrical work for safety reasons due to the many hazards of working with electricity. Such requirements may be testing, registration or licensing. Licensing requirements vary between jurisdictions.
Most electrical services
Electrical services enjoy unflagging popularity properly since arisen. Many people prefer to pay relatively little money for even simple electrician services, such as replacing light bulbs and electrical installation nietrudnych than yourself to start playing with shock, which may prove undoubtedly dangerous. The use of electrical services is also popular for the modernization of the electrical and other more complex services, as to carry out such orders, especially in the case of larger objects, very often you need to have the appropriate permissions, you can have only trained electrician.