Correct Answer - Option 4 : Silver
Concept:
Conductors are the substances through which a flow of current i.e. the flow of free electrons can be set up easily. The number of free electrons present in the substances decides its conductivity.
Properties of good conductor:
- Low resistance
- Low specific resistance or resistivity
- Low specific gravity
- High conductivity
Explanation:
Silver is the best conductor of electricity. Even though it is the best conductor of electricity, there are two reason silver is not used very frequently over other conductors:
1) It is a precious metal and thus has a high price for the amount of material used and
2) It corrodes or oxidizes easily.
Copper (Cu) is commonly used when oxidation is not an issue, such as home wiring and in most electric motors.
Gold (Au) is almost always used if oxidation is an issue. It is very common in electronic connectors and printed circuit boards to use gold plating to get past the corrosion issues.
