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प्रश्न
For what purpose are the transformers used? Can they be used with a direct current source?
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उत्तर
The purpose of the transformer is to step up or step down the a.c. voltage.
No, a transformer cannot be used with a direct current source.
संबंधित प्रश्न
Derive an expression for ratio of e.m.f.s and currents in terms of number of turns in primary and secondary coil.
State the principle of the step-down transformer and its working.
The following diagram in Fig. 10.44 shows a coil X connected to a sensitive centre –zero galvanometer G and a coil P connected to a battery through a switch S.
(a) Describe the observation when the switch S is (i) closed suddenly, (ii) then kept closed, (iii) finally opened.
(b) Name and state the law which explains the above observations.
The secondary windings of a transformer in which the voltage is stepped down are usually made of thicker wire than the primary. Explain why.
Describe briefly and two energy losses, giving the reasons for their occurrence in actual transformers ?
Name three losses of energy in a transformer. How are they minimized?
Distinguish between Step up and Step Down Transformer.
Which among the following, is not a cause for power loss in a transformer?
Electrical energy is transmitted over large distances at high alternating voltages. Which of the following statements is (are) correct?
- For a given power level, there is a lower current.
- Lower current implies less power loss.
- Transmission lines can be made thinner.
- It is easy to reduce the voltage at the receiving end using step-down transformers.
A transformer operating at primary voltage 8 kV and secondary voltage 160 V serves a load of 80 kW. Assuming the transformer to be ideal with purely resistive load and working on unity power factor, the loads in the primary and secondary circuit would be:
