A scientist observes that the electrical resistance of a superconducting material drops to zero when the material is cooled to very low temperatures. Which of the following statements best describes what the scientist is observing? The scientist is observing the electrical power of a superconductor.
The scientist is observing the temperature of a superconductor.
The scientist is observing an intensive property of a superconductor.
The scientist is observing an extensive property of a superconductor

The scientist is observing an intensive property of a superconductor.

Explanation:

An intensive property is a bulk property of matter. This means that an intensive property does not depend on the amount of substance present in the material under study. Typical examples of intensive properties include; conductivity, resistivity, density, hardness, etc.

An extensive property is a property that depends on the amount of substance present in a sample. Extensive properties depend on the quantity of matter present in the sample under study. Examples of extensive properties include, mass and volume.

Resistance of a superconducting material has nothing to do with the amount of the material present hence it is an intensive property of the superconductor.

The scientist is observing an intensive property of a superconductor.

Explanation:

its the only one that makes logical sense

pure substance: iron,copper

impure substance: water,charcoal

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