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प्रश्न
Name two factors on which the magnitude of an induced e.m.f. in the secondary coil depends.
उत्तर
The magnitude of e.m.f. induced in the secondary coil depends on the following two factors:
- The ratio of the number of turns in the secondary coil to the number of turns in the primary coil (i.e., turns ratio).
- The magnitude of e.m.f applied in the primary coil.
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.
Which coil of a step up transformer is made thicker and why?
How are the e.m.f in the primary and secondary coils of a transformer related with the number of turns in these coils?
State the factors on which the frequency of the alternating e.m.f. depends.
(i) Draw a clear labelled diagram of an electric bell.
(ii) Explain in brief, its working.
(iii) What material is used for the core of an electric bell? State the reason.
A transformer lowers e.m.f. from 220 V to 15 V. If 400 W power is given in primary, calculate (i) the current in primary coil and (ii) the current in secondary coil.
Give the advantage of AC in long distance power transmission with an illustration.
A step-down transformer connected to the main supply of 220 V is used to operate 11V,88W lamp. Calculate
- Voltage transformation ratio and
- Current in the primary
Read the following paragraph and answer the question:
Long distance power transmissions
The large-scale transmission and distribution of electrical energy over long distances is done with the use of transformers. The voltage output of the generator is stepped up. It is then transmitted over long distances to an area sub-station near the consumers. There the voltage is stepped down. It is further stepped down at distributing sub-stations and utility poles before a power supply of 240 V reaches our homes.
A power transmission line feeds input power at 2300 V to a step down transformer with its primary windings having 4000 turns. The number of turns in the secondary in order to get output power at 230 V are ______.
Define a Transformer.
