Question

How do we measured super conductor and what is the formula of it and where is found the super conductor

Answer 1

Superconductors are "hypothetical" conductors having zero electrical resistance and hence being the best conductors possible. There are no ideal superconductors. However a few examples of conductors whoze electrical resistance is close to zero are as follows:
1. Chemical elements (e.g. mercury or lead)
2. Alloys (such as niobium-titanium, germanium-niobium, and niobium nitride)
3. Ceramics (YBCO and magnesium diboride)
etc.