Conductivity Ratio: Understanding Temperature Dependence
The ratio of thermal conductivity ($k$) to electrical conductivity ($\sigma$) is related to the physical properties of a material. This ratio, when multiplied by temperature ($T$), forms the Lorenz number ($L$):
$ L = \frac{k}{\sigma T} $
The Wiedemann-Franz law states that for metals, the Lorenz number ($L$) is approximately constant at high temperatures. However, a more detailed analysis shows that $L$ is fundamentally dependent on temperature ($T$), especially at lower temperatures.
Key Dependency Analysis
- Temperature: The ratio of thermal and electrical conductivities (Lorenz number) is primarily considered a function of temperature. This dependency is predicted by theoretical models and observed experimentally.
- Mean Free Path: While the mean free path influences both thermal and electrical conductivities individually, it is not the sole factor determining their ratio. Its temperature dependence contributes to the overall temperature dependence of the ratio.
- Density: Material density does not directly determine the ratio of thermal to electrical conductivities.
- Fermi Energy: Fermi energy is crucial for understanding electrical and thermal properties in metals, but the ratio itself is more directly linked to temperature variations.
Therefore, the ratio is fundamentally dependent on temperature.
Similar Questions
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- The expression $C_V = 3R$ represents :
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- Which of the following relation gives the potential energy of a diatomic molecule ?
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Important Questions from Mixed Topic (CUET PG)
- Who was the founder of Bolshevik Communist party?
- What is the key guide to statecraft in the realist tradition?
- Chronologically arrange the events in the Cold War period.
A. Berlin Wall is constructed
B. Communist China joins the UN
C. Soviet invasion of Czechoslovakia
D. Berlin Blockade
Choose the correct answer from the options given below: Morgenthau's principles of political realism are:
A. Politics is rooted in permanent and unchanging human nature which is basically self centred, self-regarding and self-interested
B. Politics is an autonomous sphere of action and cannot therefore be reduced to morals
C. International Politics is an arena of conflicting self-interests
D. The ethics of international relations is situational ethics which is very different from private morality
Choose the correct answer from the options given below:Who among the following political thinkers consider the anarchical self help system to be a compelling factor for States to maximise their relative power positions?
