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Explain step up and step down transformer? - Physics

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Explain step up and step down transformer?

संक्षेप में उत्तर
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उत्तर

  1. Step-up transformer:
    a.
    A transformer that converts a low voltage at high current into a high voltage at low current is called a step-up transformer.
    b. In a step-up transformer, the number of turns in secondary coil NS is greater than the number of turns in primary coil NP. In this transformer, eS > eP and IS < IP.  
    c. The primary coil is made from a thick insulated copper wire so that it can sustain the high current. The secondary coil is made of a thin insulated wire.
    d. Current through secondary is less than primary. 
  2. Step down transformer:
    a. A transformer which converts a high voltage at low current into a low voltage at high current is called a step-down transformer.
    b. In step down transformer, the number of turns in the secondary coil NS is less than the number of turns in the primary coil NP. In this transformer eS < eP and IS > IP.
    c. The primary coil is made of a thin insulated wire and the secondary coil is made from thick wire so that it can sustain the high current.  
    d. Current through primary is less than secondary. 
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अध्याय 12: Electromagnetic Induction - Short Answer II

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संबंधित प्रश्न

Derive an expression for e.m.f. and current in terms of turns ratio


State the principle of transformer working with the help of a diagram


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Why is the core of a transformer laminated?


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State two factors on which the magnitude of induced e.m.f. depend.


How are the e.m.f in the primary and secondary coils of a transformer related with the number of turns in these coils?


The secondary windings of a transformer in which the voltage is stepped down are usually made of thicker wire than the primary. Explain why.


Why is the iron core of a transformer made laminated (thin sheets) instead of being in one solid piece?


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Name two kind of energy loss in a transformer. How is it minimized?


State the underlying principle of a transformer. How is the large scale transmission of electric energy over long distances done with the use of transformers?


State the principle of working of a transformer. Can a transformer be used to step up or step down a d.c. voltage? Justify your answer.


Draw a labeled diagram of a full wave rectifier circuit. State its working principle. Show the input-output waveforms ?


What is the function of a step-up transformer?


Why is the core of a transformer made of soft iron?


Draw a labelled diagram to show the various parts of a step-up transformer and step down transformer.


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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.


A transformer lowers e.m.f. from 220 V to 15 V. If the number of turns in primary are 3520, how many turns are in the secondary coil?


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Distinguish between Step up and Step Down Transformer.


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The transformation ratio in the step-up transformer is ______.

The loss of energy in the form of heat in the iron core of a transformer is ______.

A transformer is employed to ______.

The transformer voltage induced in the secondary coil of a transformer is mainly due to ______.

A transformer works on the principle of ______.


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Read the following paragraph and answer the question:


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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.

We need to step-up the voltage for power transmission, so that ______.


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.

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Explain why core of a transformer is always laminated.


How do the input and output powers in a transformer compare? State the assumption made.


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