Question

A substance has zero resistance below one kelvin. What is such a substance called?
A)superconductor
B)conductor
C)semiconductor
D)insulator

Answer 1

Hint: A superconductor is a material that conducts electricity or transports electrons from one atom to another without any resistance. After a critical temperature is reached, the substance will not release energy in another form, say heat or sound. The resistance of a superconductor decreases as the temperature decreases.

Complete step-by-step solution:
When a superconductor has reached its critical temperature, it doesn’t release energy in any form. The electric resistivity of a metallic conductor decreases gradually as temperature is lowered. In ordinary conductors, such as copper, silver, etc. The decrease in temperature is limited by impurities and other defects. Whereas in a superconductor, the resistance of the material decreases abruptly to even zero when the material is cooled below its critical temperature.
Therefore, the correct option is option a
Additional information:
Materials that form as superconductors come in two different forms. One form of a superconductor is metals or alloys of the metals. Alloy is a combination of two or more metals. The second form of the superconductor will be the ceramic-like materials. Good examples for the metal section include mercury, niobium, tin, lead, etc. Examples for ceramic-like metals will be a lanthanum-barium-copper oxide, yttrium-barium-copper oxide.at the critical temperature, the electrons in the material can move freely through the material. Superconductors are really better than ordinary conductors and very expensive compared to the ordinary ones.

Note: The greatest drawback of superconductors is that they only function as a good material at temperatures lower than its critical temperature. The superconducting material is therefore coupled with some active or passive cryogenic cooling when any application is used.