Question

The effectiveness of a material for use in superconductivity applications depends on its:

• A. Optical properties
• B. Magnetic properties
• C. Critical temperature
• D. Electrical resistivity

Hint:

Think superconductors? Think cold! The higher the critical temperature, the easier (and cheaper) it is to use them.

Answer 1

The Correct Option is C

Superconductivity is the phenomenon where a material exhibits zero electrical resistance and expels magnetic fields when cooled below a certain temperature. This temperature is known as the critical temperature (\(T_c\)).
The value of the critical temperature determines how practical a superconducting material is for real-world applications. Materials with higher \(T_c\) values are more favorable because they require less cooling, reducing both energy consumption and system cost. For instance, high-temperature superconductors can operate at liquid nitrogen temperatures (~77 K), making them more suitable for technological applications such as MRI machines, maglev trains, and superconducting cables.
Other options clarified:

• (A) Optical properties are not relevant to superconductivity.
• (B) While magnetic effects (like the Meissner effect) are characteristics of superconductors, they are outcomes — not determinants of suitability.
• (D) Electrical resistivity becomes zero in superconductors, but this alone doesn’t determine usability — the key is at what temperature this occurs.

Thus, the effectiveness of a material for superconducting use primarily depends on its critical temperature.