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प्रश्न
A 10 m long wire of a particular material is of resistance 5Ω What will be the resistance if the wire is stretched to double its length?
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उत्तर
On stretching the wire to double its length, the length is doubled and its area of cross-section is reduced to half. So the resistance becomes four times i.e. the resistance of wire will become: 4 × 5Ω = 20 Ω.
संबंधित प्रश्न
The values of current (I) flowing through a given resistor of resistance (R), for the corresponding values of potential difference (V) across the resistor are as given below:
| V (volts) | 0.5 | 1.0 | 1.5 | 2.0 | 2.5 | 3.0 | 4.0 | 5.0 |
| I (amperes) | 0.1 | 0.2 | 0.3 | 0.4 | 0.5 | 0.6 | 0.8 | 1.0 |
Plot a graph between current (I) and potential difference (V) and determine the resistance (R) of the resistor.
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The other name of potential difference is:
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