Thermal diffusivity: nature and classification. Identify the most accurate description of thermal diffusivity (α = k/(ρ·cᵖ)). Select the correct statement.
Mechanical Engineering
Heat Transfer, Refrigeration and Air Conditioning
Difficulty: Easy
Choose an option
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AIt is a function of temperature.
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BIt is a physical property of a substance.
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CIt is a dimensionless parameter.
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DAll of these.
Answer
Correct Answer: It is a physical property of a substance.
Explanation
Facts about thermal diffusivityα = k/(ρ·cᵖ) has units of m²/s (not dimensionless).It is a material property and commonly varies with temperature (so it can be temperature-dependent).
Option analysisA can be true in practice, but the safest classification is that α is a material property.C is incorrect because α is not dimensionless.D is therefore incorrect because it includes a wrong statement.
Final AnswerIt is a physical property of a substance.