Same chapter2 marksDifficulty: Medium
Why does a transformer not work on a direct-current supply?
Electromagnetism
3 marksDifficulty: Medium
A transformer has 200 turns in its primary and 1000 turns in its secondary. If the primary is connected to a 220 V a.c. supply, find the secondary voltage and state the type of transformer.
Original Khojo Papers practice question — not from a past board paper.
Answer
1100 V, and it is a step-up transformer.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The ratio of the voltages equals the ratio of the turns, so V2 = 220 × 1000 ÷ 200 = 1100 V. A secondary voltage higher than the primary means the transformer steps up.
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