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प्रश्न
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उत्तर
According to Ohm's law, the current flowing in a conductor is directly proportional to the potential difference across its ends provided the physical conditions and temperature of conductor remains constant.
Limitations of Ohm's law:
1. Ohm's law does not apply to conductors such as diode, radio valves, metal rectifiers, where electricity passes through gases.
2. Ohm's law is applicable only when the physical conditions remain constant.
3. Ohm's law is applicable only when the temperature of the conductor is constant.
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संबंधित प्रश्न
What is an Ohmic resistor?
Write the SI unit of resistivity
State Ohm’s law and draw a neat labelled circuit diagram containing a battery, a key, a voltmeter, an ammeter, a rheostat and an unknown resistance to verify it.
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What are non-ohmic conductors? Give one exmaple. Draw a current-voltage graph for a non-ohmic conductor.
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Reason: V = IR is the equation which defines resistance.
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