Physics · Series and parallel combinations of resistors, temperature dependence of resistance
For a metallic wire, the ratio (where, applied potential difference and current
For a metallic wire, the ratio \( \frac{V}{i} \) (where, \( \mathbf{V}= \) applied potential difference and \( \mathbf{i}= \) current flowing
- A. is independent of temperature
- B. increases as the temperature rises
- C. decreases as the temperature rises
- D. increases or decreases as temperature rises depending upon the metal.
Step-by-step solution
For a metallic wire, the ratio V/i is the resistance R. According to Ohm's law, R = V/i, and for metals, resistivity increases with temperature due to increased lattice vibrations, leading to a positive temperature coefficient. Thus, as temperature rises, resistance increases, so V/i increases.
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