why do we need an a.c current for powering our homes(most house hold appliances run on ac)?

Question

whats the advantages of using a.c over dc current

Answer 1

AC is easier and more efficient ot transmit over long distances. The amount of power being transmitted over a transmission line si the product of the voltage times the current, and the power loss in a transmission line is the line resistance times the square of the current.
P = I*E
Loss = I² * R
The obvious strategy is to make teh voltage as high as possible and keep the current as low as possible. But this is very difficult to do with DC. With AC, a simple transformer will easily 'step up' the voltage on the transmission end and step it back down to safer levels at the consumption end.

Doug

Answer 2

When transmitting power, it's far more efficient to have a high voltage and a low current, because,

Power lost = Current^2 * Resistance

Since nothing can be done about the resistance of the transmission cables, the best thing to do is to step the voltage up (and therefore the current down) using a transformer. Since transformers only work when using AC electricity, it makes for a much more efficient distribution system.

Answer 3

The old Edison/Tesla debate. Edison was able to propigate the public's fear of electrocution by direct current by alligations that AC's alternating current was the safer alternative. Though both AC and DC distribution systems have been successfully employed here in America, AC has won out, much to the delight of transformer manufacturers the world over.

Answer 4

AC can be transmitted over much greater distances.

Answer 5

An ac current is safer than a dc current. And it can be transmitted over long distances very efficiently.
The ac current flows one way, whereas a dc current flows two ways or splits up. There fore, ac current is more efficient than the dc current.