Which among the following has the least thermal conductivity?

The correct answer is superconductor.

Key Points

• Superconductors have zero electrical resistance and expel magnetic fields when cooled below a characteristic critical temperature.
• Superconductors are used in applications requiring highly efficient electrical conductors.
• They are known for their ability to carry electricity without loss, making them ideal for applications such as MRI machines and maglev trains.
• Because of their unique properties, superconductors have the lowest thermal conductivity compared to metals, semiconductors, and alloys.

Important Points

• Thermal conductivity is a property that indicates the ability of a material to conduct heat.
• Materials with high thermal conductivity transfer heat quickly, while those with low thermal conductivity transfer heat slowly.
• Superconductors, despite their excellent electrical properties, have low thermal conductivity.

Additional Information

• Metal: Metals like copper and aluminum have high thermal conductivity, which is why they are used in heat sinks and cooking utensils.
• Semiconductor: Semiconductors like silicon have moderate thermal conductivity. They are used in electronic devices due to their electrical properties rather than their thermal properties.
• Alloy: Alloys are mixtures of metals and have varying thermal conductivities. For instance, brass and bronze have moderate thermal conductivity.