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प्रश्न
State the principle of a transformer.
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उत्तर
It is based on the principle of ‘electromagnetic induction’. The magnitude of induced e.m.f. is given by the formula.
`"No. of turns in primary coil"/"No.of. turns in secondary coil" = "E.m.f. in primary"/"E.m.f in secondary"`
Neglecting power losses
Elective power fed in the primary (input) = Elective power produced in secondary (output)
or Ep × iP = Es × is
`"E"_"p"/"E"_"s" = "i"_"s"/"i"_"p"`
संबंधित प्रश्न
State the principle of transformer working with the help of a diagram
Name the transformer used in the power transmitting station of a power plant.
You are required to make an electromagnet from a soft iron bar by using a cell, an insulated coil of copper wire and a switch. (a) Draw a circuit diagram to represent the process. (b) label the poles of the electromagnet.
Explain the significance of Lenz’s law to show the conservation of energy in electromagnetic induction.
In an ideal transformer, an output of 66 kV is required when an input voltage of 220 V is available. If the primary has 300 turns, how many turns should the secondary have?
Assertion: A transfonner cannot work on D.C. supply.
Reason: D.C. changes neither in magnitude nor in direction.
A transformer is essentially an a.c. device. It cannot work on d.c. It changes alternating voltages or currents. It does not affect the frequency of a.c. It is based on the phenomenon of mutual induction. A transformer essentially consists of two coils of insulated copper wire having different numbers of turns and wound on the same soft iron core.
The number of turns in the primary and secondary coils of an ideal transformer is 2000 and 50 respectively. The primary coil is connected to a main supply of 120 V and secondary coil is connected to a bulb of resistance 0.6 Ω.
The value of current in the bulb is ______.
The primary coil having NP turns of an ideal transformer is supplied with an alternating voltage VP. Obtain an expression for the voltage VS induced in its secondary coil having NS turns.
