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प्रश्न
The input and output voltage of a transformer are 220 V and 44 V respectively. Find: the turns ratio.
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उत्तर
We know that
`"E"_"p"/"E"_"s" = "N"_"p" / "N"_"s"`
So turns ratio
`"N"_"s" / "N"_"p" = 44/ 220`
= 1.5
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संबंधित प्रश्न
The teachers of Geeta’s school took the students on a study trip to a power generating station, located nearly 200 km away from the city. The teacher explained that electrical energy is transmitted over such a long distance to their city, in the form of alternating current (ac) raised to a high voltage. At the receiving end in the city, the voltage is reduced to operate the devices. As a result, the power loss is reduced. Geeta listened to the teacher and asked questions about how the ac is converted to a higher or lower voltage.
1) Name the device used to change the alternating voltage to a higher or lower value. State one cause for power dissipation in this device.
2) Explain with an example, how power loss is reduced if the energy is transmitted over long distances as an alternating current rather than a direct current.
3) Write two values each shown by the teachers and Geeta.
Explain why an induced current must flow in such a direction so as to oppose the change producing it.
Explain the significance of Lenz’s law to show the conservation of energy in electromagnetic induction.
Mention the two characteristic properties of the material suitable for making core of a transformer.
The output power in step-up transformer used in practice is ______.
A 220 V input is supplied to a transformer. The output circuit draws a current of 2.0 A at 440 V. If the ratio of output to input power is 0.8, then the current drawn by primary winding is ______.
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.
Which of the following statement is true?
The primary coil of a transformer has 800 turns and the secondary coil has 8 turns. It is connected to a 220 V ac supply. What will be the output voltage?
In an ideal transformer, the turns ratio is \[\frac {N_p}{N_s}\] = \[\frac {1}{2}\]. The ratio Vs : Vp is equal to (the symbols carry their usual meaning) ______.
A 12 V, 60 W lamp is connected to a 220 V AC supply using an ideal transformer. Find the primary current.
