CBSE Class 12 · 2014 · Delhi · Alternating CurrentVery Short Answer

Why is the use of a.c. voltage preferred over d.c. voltage? Give two reasons.

Solution

An alternating voltage can be raised or lowered almost without loss by a transformer, so power can be transmitted at high voltage — hence low current and small

I^{2} R

loss — and then stepped down for use. Also, a.c. generators are simpler and cheaper than d.c. generators because they need no commutator. These make a.c. preferable to d.c.

CBSE Class 12 Board · 2014 · Delhi · Subjective

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