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प्रश्न
What are step-up and step-down transformers?
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उत्तर
- A transformer that increases the voltage by decreasing current is known as a step-up transformer.
- A transformer that decreases the voltage by increasing the current is a step-down transformer.
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संबंधित प्रश्न
Derive an expression for e.m.f. and current in terms of turns ratio
Express the turn ratio in terms of voltages.
The primary coil of an ideal step-up transformer has 100 turns and the transformation ratio is also 100. The input voltage and power are 220 V and 1100 W, respectively. Calculate the
(a) number of turns in secondary
(b) current in the primary
(c) a voltage across secondary
(d) current in secondary
(e) power in secondary
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An ideal transformer converts 220 V a.c. to 3.3 kV a.c. to transmit a power of 4.4 kW. If primary coil has 600 turns, then alternating current in secondary coil is ______.
