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प्रश्न
Use the data in the Table given below to answer the following –
Which material is the best conductor?
Table give below Electrical resistivity of some substances at 20°C
Electrical resistivity of some substances at 20°C | ||
− | Material | Resistivity (Ω m) |
Conductors |
Silver | 1.60 × 10−8 |
Copper | 1.62 × 10−8 | |
Aluminium | 2.63 × 10−8 | |
Tungsten | 5.20 × 10−8 | |
Nickel | 6.84 × 10−8 | |
Iron | 10.0 × 10−8 | |
Chromium | 12.9 × 10−8 | |
Mercury | 94.0 × 10−8 | |
Manganese | 1.84 × 10−6 | |
Alloys |
Constantan (alloy of Cu and Ni) |
49 × 10−6 |
Manganin (alloy of Cu, Mn and Ni) |
44 × 10−6 | |
Nichrome (alloy of Ni, Cr, Mn and Fe) |
100 × 10−6 | |
Insulators | Glass | 1010 − 1014 |
Hard rubber | 1013 − 1016 | |
Ebonite | 1015 − 1017 | |
Diamond | 1012 − 1013 | |
Paper (dry) | 1012 |
उत्तर १
It can be observed from the Table given in the question that the resistivity of silver is the lowest among the listed materials. Hence, it is the best conductor.
उत्तर २
Silver is the best conductor as its resistivity (ρ) is the least, i.e., 1.60 × 10-8 Ωm.
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