Question
What is AC current and DC current? Why is AC voltage preferred compared to DC voltage in practice?
✓
Answer
→AC current : The current that varies like a sine or cosine function with time is called AC current.
→DC current : The current that remains constant with time is called DC current.
→AC voltage is preferred more than DC voltage in practice, because...
(1) Using transformers, the value of AC voltage can be changed easily.
(2) Electrical energy can be transmitted economically (and easily) over long distances.
→DC current : The current that remains constant with time is called DC current.
→AC voltage is preferred more than DC voltage in practice, because...
(1) Using transformers, the value of AC voltage can be changed easily.
(2) Electrical energy can be transmitted economically (and easily) over long distances.
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