What is AC Current?
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Alternating current (AC) is an electric currentwhich periodically reverses direction, in contrast to direct current (DC) which flows only in one direction. Alternating current is the form in which electric power is delivered to businesses and residences, and it is the form of electrical energy that consumers typically use when they plug kitchen appliances, televisions, fans and electric lamps into a wall socket. A common source of DC power is a battery cell in a flashlight. The abbreviations AC and DC are often used to mean simply alternating and direct, as when they modify current or voltage.
The usual waveform of alternating current in most electric power circuits is a sine wave, whose positive half-period corresponds with positive direction of the current and vice versa. In certain applications, like guitar amplifiers, different waveforms are used, such as triangular or square waves. Audio and radio signals carried on electrical wires are also examples of alternating current. These types of alternating current carry information such as sound (audio) or images (video) sometimes carried by modulation of an AC carrier signal. These currents typically alternate at higher frequencies than those used in power transmission.
Electrical energy is distributed as alternating current because AC voltage may be increased or decreased with a transformer. This allows the power to be transmitted through power lines efficiently at high voltage, which reduces the energy lost as heat due to resistance of the wire, and transformed to a lower, safer, voltage for use. Use of a higher voltage leads to significantly more efficient transmission of power. The power losses ({\displaystyle P_{\rm {w}}}) in the wire are a product of the square of the current ( I ) and the resistance (R) of the wire
This means that when transmitting a fixed power on a given wire, if the current is halved (i.e. the voltage is doubled), the power loss due to the wire's resistance will be reduced to one quarter.
The power transmitted is equal to the product of the current and the voltage (assuming no phase difference)
Consequently, power transmitted at a higher voltage requires less loss-producing current than for the same power at a lower voltage. Power is often transmitted at hundreds of kilovolts on pylons, and transformed down to tens of kilovolts to be transmitted on lower level lines, and finally transformed down to 100 V – 240 V for domestic use.
What is meant by AC current?
Alternating current (AC) is an electric currentwhich periodically reverses direction, in contrast to direct current (DC) which flows only in one direction. ... The abbreviations ACand DC are often used to mean simplyalternating and direct, as when they modifycurrent or voltage.
Why is AC current used?
The major advantage that AC electricity has over DC electricity is that AC voltages can be readily transformed to higher or lower voltage levels, while it is difficult to do that with DC voltages. ... This is because the high voltages from the power station can be easily reduced to a safer voltage for use in the house.
Why DC current is not used in homes?
Large transformers are used to run transmission lines at high voltages in order to keep losses to a minimum. But high voltage is dangerous, particularly to life, so bringing it into a house would not be an acceptable risk. ... DC arcs do not "quench" as easily (becausevoltage does not go through zero).
Who invented AC power?
Nikola Tesla
Serbian-American engineer and physicistNikola Tesla (1856-1943) made dozens of breakthroughs in the production, transmission and application of electric power. He invented the first alternating current (AC) motor and developed AC generation and transmission technology.
Who is the real father of electricity?
Michael Faraday
A self-taught scientist, Michael Faraday (1791-1867) excelled in chemistry and physics to become one of the most influential thinkers in history. He's been called the "father of electricity," (Nikola Tesla and Thomas Edison also wear that crown) and his appetite for experimenting knew no bounds.
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