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Alternating current is preferred mainly because electrical power for homes and industry is often used many miles away from the power station. Cables of the power distribution network have electrical resistance to current flow and they heat up thus wasting energy. Reducing the waste heat to a minimum is done by keeping the transmitted current to a minimum since POWER in Watts= Current (I) x Voltage (V).
Hopefully you can see that the same power can be transmitted by upping the voltage and lowering the current using this formula
This trick is done using a 'step up' transformer, these installations can be up to 99 % efficient but can only work with currents that are constantly changing polarity. Alternating current is produced in the power station using 'alternators' by rotating magnets past coils of wire.
Note
Alternating current seems to be pointless, it's like taking a step forward and immediately taking one step back. In practice it is like making fire by rubbing a wooden rod backwards and forwards between your hands:- you still make heat!
By the way Thomas Edison had big problems in understanding AC, so you are not alone.
Once the power has been transmitted across country at 300,000 volts for example it is finally reduced in pressure in stages through a series of 'Step down' Transformers.
These devices make a constant humming noise and can be seen attached to wooden poles feeding remote farms and houses.
It is not possible to do this with direct current (DC) as Edison found out when he tried to send his DC to houses a mile away from his first power station. By the time it reached his customers the voltage had dropped and the lights were dim.
A Serbian engineer called Nicola Tesla tried to convince Edison to try using AC but was subsequently fired. Tesla realized that AC was the future and teamed up with Westinghouse in the USA and Ferranti in the UK.
If you want to know how transformers work see Michael Faraday.
This has to do with the transmission of electricity. The power company supplies power in AC, rather than DC, because they can transmit electricity much further distances using AC. This enables the power company to build power plants in remote locations, rather than having to build them right in your neighborhood. BESIDE TRANSMISIION THERE IS A FACT OF DISTRIBUTION TRANSMISSION IS 500KV DISTRIBUTION IS 16KV. WITH DC IT WOULD BE CONVERTED SOME WHAT MUCH LESS EFFICIENT. By using ac we can step up or step down the voltage as per requirement.
There are a few reasons.
1) Easier to generate (by rotating a standard engine)
2) Stable clock rate (usable by devices to keep track of time)
3) Easy to transform (into higher or lower voltage)
4) Easy to change into direct current (e.g. diode bridge)
5) AC power can be carried long distances by increasing the voltage and lowering the current. Early electrical distribution did not have the technology to efficiently change AC to DC and back again.
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It's much easier to generate alternating current (AC) from mechanical generators. In fact, to generate direct current (DC) from turbines, it is necessary to generate AC and then convert it to DC.
It's easier to design powerful motors using AC. Industrial systems often use 3 phase electricity where three separate currents are sent with the phase of each current 120o from the next.
It's much easier to change voltages with an alternating current; standard transformers only work with alternating current. Electrical power is usually distributed around the country at very high voltages (as this is more efficient) and then reduced to "domestic" voltage levels at substations. This system would not be possible with DC.
Albert Einstein had an argument saying that it would be better to use Direct Current (DC) and even created an experiment making an electronic chair, but another scientist said using Alternating Current (AC) was better . This was both for the use of supplying electricity to homes through cables and the governments decided to use AC this is because it can travel quicker through light wires. Recently it has been discovered that Einstein probably was right and using DC would have been better but that it would cost to much to change all of the electronic cables.
A long story really! Albert Einstein had an argument saying that it would be better to use Direct Current (DC) and even created an experiment making an electronic chair, but another scientist said using Alternating Current (AC) was better . This was both for the use of supplying electricity to homes through cables and the governments decided to use AC this is because it can travel quicker throught light wires. Recently it has been discovered that Einstein probaly was right and using DC would have been better but that it would cost to much to change all of the electronic cables. And there is your long answer to your question!!!
Because A.C. can go farther without dissipating as heat. Much easier to change from low to high voltage and back down.
Answer
Alternating current is widely used because its voltage can be easily and efficiently increased or decreased using transformers. Transformers are a.c. machines, and will not work with d.c.
For this reason, most transmission systems use a.c. However, d.c. transmission has less losses than a.c. transmission, but is more expensive (its high voltage is achieved by transforming a.c. to a high voltage then rectifying it -the extra equipment making it expensive). However, for very long transmission lines, the expense is worth it because the line losses are lower.
The advantage of using AC instead of DC in our homes is that AC electricity can be carried over long distances because the voltage can be stepped up easily during transit and then stepped down at the point of use while DC electricity can not easily be converted like that. This means that DC needs to be produced close to the point of use.
If we had DC electricity supplying our homes, we would have to have a power plant every few miles. AC electricity, on the other hand, can be produced in a power plant that is hundreds of miles away.
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Why do people use alternating current in your nomes today?
The use of alternating current permits voltages to be altered via transformers, so for efficiency the voltage at the generator can be stepped up for transmission to reduce losses and cost, then stepped down again at the user's end to whatever voltage is needed. For safety reasons homes use a lower voltage than does industry. Multi-phases can be used to give more than one voltage from the same supply without transformers.
Why is there a need for our water supply to be managed and distributed?
Because it needs to be purified, sterilised and distributed to homes.
Generators can produce two types of electric current?
Absolutely! Generators can indeed produce two types of electric current: alternating current (AC) and direct current (DC). Let me break it down for you. First up, we've got Alternating Current (AC). This is the kind of electricity you'll find in most homes and businesses. AC changes direction periodically, meaning the flow of electrons alternates back and forth. It's like a little dance where the electrons keep switching partners, and it's super efficient for transmitting electricity over long distances. That's why the power from your local utility company is usually AC. On the flip side, we have Direct Current (DC). This type of current flows in a constant direction, like a straight line. You'll find DC in batteries – it's the juice that keeps your gadgets powered up. While it's not as great for long-distance transmission, DC has its perks, especially for certain electronic devices that prefer a steady and unchanging flow of electricity. So, in a nutshell, generators can play both sides of the current game, producing either AC or DC, depending on the application. It's like having a versatile musician who can rock out with different tunes depending on the audience. Cool, right?
What is the definition of ac electricity and dc electricity?
AC means alternating current and DC means direct current. The amplitude of AC voltage and current varies with time. Traditional AC electricity used in homes in the United States is a 60 Hertz sine wave. This means that 60 cycles of a sine wave occur every 1 second. Since AC voltage varies with time, the amplitude at each instant is different. The voltage changes from 0 to +Vpeak to 0 to -Vpeak and so on. Since the amplitude is always changing, the voltage quoted for AC such as 120 Vac for US homes is an average known as the Root Mean Square (RMS). The general formula for determining the amplitude of the voltage at any given time is: Vinst = Vpeak x sin(t) where Vinst is the instantaneous voltage at time t, Vpeak is the peak voltage, and t is the time. The relationship between Vrms and Vpeak for a sine wave is given by the formula Vrms = Vpeak / square root (2), so Vrms = Vpeak x 0.707 DC electricity does not vary with time. The voltage and current are constant at all times.
What are the types of and uses for a transformer?
There are two types of transformers:- 1. Step-up transformer & 2. Step-down transformer. A transformer used to increase the voltage is called Step-up transformer. A transformer used to decrease the voltage is called Step-down transformer. Uses of step-up transformer:- in power supply stations, in picture tubes of TV, computer monitors, halogen lights, etc. Uses of step-down transformer:- in supply of electricity to homes, in the power supply to the low voltage devices like radio, music systems which are run by AC mains.
What is the electric current supplied to most homes celled?
The electric current supplied to most homes is alternating current (AC).
What type of current is in homes?
AC alternating current
Is home lighting AC or DC?
Electricity supply services for lighting and other electrial appliances used in homes are alternating current (ac).
What type of current is used in homes?
Both ac and dc current are used in our homes. But only low frequency (50 or 60 Hz) ac current is furnished by the power company. Electrical devices in our homes that require dc current usually have built in ac to dc rectifiers. we get electricity into home from main power supply as AC current.according to our electrinic devices select what type of current is suitable for it.for example,Ac power supply used to Tetevision,computers etc.Inside the devices,AC current convert into DC current.
What did alternating electrical current effect in the 1920?
The widespread adoption of alternating current in the 1920s revolutionized the electrical power industry by allowing for the efficient transmission of electricity over long distances through high voltage power lines. This enabled the development of large-scale power grids that could supply electricity to homes, businesses, and industries, leading to improved standards of living and economic growth.
What type of electric current does a power plant generate for use in your home?
generally power plants produce ALTERNATING CURRENT,because after producing the current the are sent to substations where they are stepped up or stepped down.so a transformer is mainly used over there.for a transformer we cant supply direct current.we should supply only alternating current.so they only produce alternating current................... 4RM PRAJITH
What wave shape of the mains supply is know as?
The mains supply wave shape is known as a sine wave. It represents the alternating current that is provided by electrical utilities for powering our homes and businesses.
Electrons move from the power plant to homes in an alternating current?
Alternating current, yes. But it is not quite correct to say "electrons move to the homes... " rather, it is the CURRENT that moves to the home. It is more like a wave, where the energy is transmitted from one particle to the next.
Which invention delivered electricity to homes and businesses in the late 1800s?
alternating current
On which current does fan rotate?
Most fans operate on an alternating current (AC) as it is the standard electrical power supply in homes and buildings. However, some fans, like those in vehicles or powered by batteries, may operate on direct current (DC).
Electric current from a generating plant is?
Electric current from a generating plant is typically alternating current (AC), which flows back and forth in a rapid and regular manner. This AC current is then transmitted through power lines to homes and businesses for use in electrical appliances and devices.
Why do people use alternating current in your nomes today?
The use of alternating current permits voltages to be altered via transformers, so for efficiency the voltage at the generator can be stepped up for transmission to reduce losses and cost, then stepped down again at the user's end to whatever voltage is needed. For safety reasons homes use a lower voltage than does industry. Multi-phases can be used to give more than one voltage from the same supply without transformers.
