Question

Which of the following metals is a good conductor of electricity?
A. Silver and gold
B. Copper and aluminium
C. Tungsten
D. All of these

Answer 1

Hint: The most electrically conductive element is a group 11 element. The filament of a bulb which glows when the current flows through it is made up of tungsten.

Complete step by step answer:
Electrical conductivity of a material is its fundamental property that quantifies the ability to allow the transfer of electric charges or how strongly it conducts electric current. Electrical conductivity is the reciprocal of electrical resistivity. It is commonly denoted by the Greek letter (sigma). The SI unit of electrical conductivity is siemens per metre (\[\dfrac{S}{m}\]).
Silver is the best conductor of electricity. The free electrons in silver are freer to move than the electrons of any other element. This is due to the crystal structure of silver. However, it is not used for making wires because it is expensive and is too soft. Also, after a certain time, silver tarnishes and is less desirable for high frequencies as the exterior surface becomes less conductive.
The second most conductive element is copper, followed by gold. Copper and gold are more often used in electrical appliances as copper is less expensive and gold has a much higher corrosion resistance.
Tungsten is used to make the filament of bulbs which glows when the current flows through it. It is a good conductor of electricity. Also, aluminium is also used for making wires and is also a good conductor of electricity.

Hence, the correct answer is (D) All of these.

Note: Remember that aluminium is less frequently used for wiring at homes. The U.S. Consumer Product Safety Commission reported that the homes with aluminium wiring are 55 times more likely to have a fire hazard than the homes wired with copper.