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Direct current (d.c.) is defined as a current that
AFlows with constant magnitude in one direction
BReverses its direction at regular intervals
CKeeps changing its magnitude with time
DFlows only when light falls on the wire
Answer & Solution
Correct answer: A. Flows with constant magnitude in one direction
1. Section 9.1 defines direct current.
2. Magnitude stays the same with time.
3. It always flows in one direction.
4. So option A is correct.
_Source: Selina Concise Physics Class 9, Ch 9 Current Electricity (Mistral OCR'd PDF), section 9.1_
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