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Old Monday, November 27, 2017
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Default (D) Most of the household appliances utilize 'DC' then why we generate 'AC' at power

Please answer the question
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The main reason is that AC is easier to transport over long distances. AC can be transmitted at high voltages, thus reducing power losses.

Plus AC to DC conversion is pretty straightforward, as is conversion from low to high voltage using transformer.

If you want more details, you can search on the internet.

If you still want more details, you can explore how in America and China, they are transporting DC in some cases with power losses less than AC!
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Because a generator generates Alternating voltages..
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Because AC is easy and cheap to transform from one voltage to another using transformers. High voltage means less amperage for the same power, meaning you can do with thinner wires. But high voltage is difficult and dangerous to use. With AC, it's easy to transform 400kV from transmission lines into the 110 or 220V that you can use at home.

with new semiconductors that are now available we can - similar to switching power supplies - convert DC as well somewhat more economically. So high voltage DC transmission lines are now becoming more popular. DC has the advantage that you have no losses due to EM radiation. So the old rules are changing due to technology.

I cannot understand this: "High voltage means less amperage for the same power" Please elaborate a little
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Quote:
Originally Posted by Fatima Saleem View Post
I cannot understand this: "High voltage means less amperage for the same power" Please elaborate a little
Consider this equation:

Power = Voltage x Current

Let's say you are transmitting a power of 100W with 5V and 20A(5x20=100W).

If you increase the voltage to 50V, how much current will you need to keep the power at 100W? Ans: 2A. Similarly, if you increased the voltage to 1000V, the current will be 0.1A to keep the total power at 100W(1000x0.1=100W). This is why we say 'high voltage means less current(amperage) for the same power'

If you understood the above, you can also see why we prefer high voltage and low current to transmit electricity. The wire through which the electricity passes only 'feels' the current passing through it, not the voltage. Hence, a higher current means more power losses during transmission. So we try to reduce the amperage as much as possible to avoid power losses during transmission.
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Quote:
Originally Posted by Norymberskie View Post
Consider this equation:

Power = Voltage x Current

Let's say you are transmitting a power of 100W with 5V and 20A(5x20=100W).

If you increase the voltage to 50V, how much current will you need to keep the power at 100W? Ans: 2A. Similarly, if you increased the voltage to 1000V, the current will be 0.1A to keep the total power at 100W(1000x0.1=100W). This is why we say 'high voltage means less current(amperage) for the same power'

If you understood the above, you can also see why we prefer high voltage and low current to transmit electricity. The wire through which the electricity passes only 'feels' the current passing through it, not the voltage. Hence, a higher current means more power losses during transmission. So we try to reduce the amperage as much as possible to avoid power losses during transmission.
Thanks a lot
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