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Question
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 |
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Solution
The current-voltage graph is shown in figure.
Resistance R = `(triangle"V")/(triangle"I")`
`= ((3.0 - 0.6)"V")/((1.5 - 0.3)"A")`
`= (2.4"V")/(1.2"A") = 2 Omega`
The conductor is ohmic.
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