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प्रश्न
Answer the following question.
Distinguish between Ohmic and non-ohmic substances; explain with the help of example.
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उत्तर
| Ohmic substances | Non-ohmic substances |
| 1. Substances which obey ohm’s law are called ohmic substances | 1. Substances which do not obey ohm’s law are called non-ohmic substances. |
| 2. Potential difference (V) versus current (I) curve is a straight line. | 2. Potential difference (V) versus current (I) curve is not a straight line. |
| 3. Resistance of these substances is constant i.e. they follow linear I-V characteristic. | 3. Resistance of these substances is a function of V or I. |
| 4. Expression for resistance is, R = `"V"/"I"` | 4. Expression for resistance is, R = `lim_(Δ"l"→0)(Δ"V")/(Δ"I")="dV"/"dI"` |
| 5. Examples: Gold, silver, copper etc. | 5. Examples: Liquid electrolytes, vacuum tubes, junction diodes, thermistors etc. |
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संबंधित प्रश्न
If the potential difference across the ends of a conductor is 220 V and the resistance of the conductor is 44 Ω (ohm), then the current flowing through is _________.
- 0.2 A
- 0.5 A
- 2 A
- 5 A
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1) Name the law.
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3) Name the material used for making the connecting wire.
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(b) resistance and potential difference
(c) potential difference and electric charge
(d) current and potential difference
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Neglecting internal resistance of the cell use (> or < or =) to compare:
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