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प्रश्न
State two causes of energy loss in a transformer.
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उत्तर
Causes of energy loss in a transformer:
1) Eddy currents developed in the core.
2) Hysteresis loss because of repeated magnetisation and demagnetisation of the iron core.
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संबंधित प्रश्न
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The following table shows current in Amperes and potential difference in Volts.
What will be the nature of the graph between the current and potential difference? (Do not draw a graph.)
From the following observations taken while determining the resistance of a conductor, draw the current-voltage graph and calculate the resistance of conductor. Is the conductor ohmic?
| Ammeter reading I (in ampere) | Voltmeter reading V (in volt) |
| 0.2 | 0.4 |
| 0.3 | 0.6 |
| 0.5 | 1.0 |
| 0.8 | 1.6 |
| 1.5 | 3.0 |
Conceptual question.
Does a solar cell always maintain the potential across its terminals constant? Discuss
Exercise.
Calculate the amount of charge that would flow in 2 hours through an element of an electric bulb drawing a current of 2.5 A.
Name the instrument which is used to measure the potential difference.
