Physics
The specific resistance of copper, silver and constantan are 1.78 x 10-6 Ω cm, 10-6 Ω cm and 48 x 10-6 Ω cm respectively.
(i) Identify the best conductor.
(ii) Give reason for your answer above.
Current Electricity
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Answer
(i) The best conductor is silver because it has the lowest specific resistance among the three given materials.
(ii) Specific resistance (resistivity) indicates how strongly a material opposes the flow of electric current. A lower value of resistivity means less opposition to current flow and hence better conductivity.
Since silver has the smallest resistivity compared to copper and constantan, it allows electric current to pass most easily, making it the best conductor.
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