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प्रश्न
Temperature dependence of resistivity ρ(T) of semiconductors, insulators and metals is significantly based on the following factors:
- number of charge carriers can change with temperature T.
- time interval between two successive collisions can depend on T.
- length of material can be a function of T.
- mass of carriers is a function of T.
विकल्प
a and b
b and c
c and d
a and c
उत्तर
a and b
Explanation:
Resistivity is the intrinsic property of the substance. For a metallic conductor, resistivity is given by
`ρ = m/("ne"^2τ)`
Where n is the number of charge carriers per unit volume (number density) which can charge with temperature T and τ is relaxation time (time interval between two successive collisions) which decreases with the increase of temperature `(T oo 1/τ)`.
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संबंधित प्रश्न
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(B) The inversion temperature does not depend on the temperature of the cold junction.
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| Metal with lead (Pb) |
a `mu V"/"^oC` |
b `muV"/("^oC)` |
| Aluminium | -0.47 | 0.003 |
| Bismuth | -43.7 | -0.47 |
| Copper | 2.76 | 0.012 |
| Gold | 2.90 | 0.0093 |
| Iron | 16.6 | -0.030 |
| Nickel | 19.1 | -0.030 |
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| Silver | 2.50 | 0.012 |
| Steel | 10.8 | -0.016 |
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By increasing the temperature, the specific resistance of a conductor and a semiconductor -
