Differences b/w AC and DC

what i say is that

if current should flow in the circuit it should be a closed circuit......so it is said that in ac the direction of current changes at regelar intervals... so in our home appliances the current comes from the mains that all there is no closed circit so how does current flow in every electrical devices and also power is consumed.....
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State the question here as well....I assume AC and DC to mean currents...the most obvious one, DC is direct current and AC is alternating. I can't tell you anymore than that since I don't know what exactly you want to know about them.


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AC circuits are also closed, just like DC circuits. The only difference is that voltages do not change with time in a DC current loop.

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