Same chapter3 marksDifficulty: Medium
Why is a transformer not usable with direct current, and what are eddy currents?
Electromagnetic Induction and Alternating Currents
3 marksDifficulty: Medium
Define the root mean square value of an alternating current and state its relation to the peak value.
Original Khojo Papers practice question — not from a past board paper.
Answer
The root mean square value of an alternating current is the value of the steady direct current that would produce the same heating effect in the same resistance over the same time. For a sinusoidal current it is the peak value divided by √2, that is 0.707 times the peak value.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
An ammeter in an a.c. circuit reads the rms value.
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