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प्रश्न
Answer the following question.
Explain the term thermal resistance. State its SI unit and dimensions.
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उत्तर
- Consider expression for conduction rate,
`"P"_"cond" = "kA" ("T"_1 - "T"_2)/"x"`
`=> ("T"_1 - "T"_2)/"P"_"cond" = "x"/"kA"` .....(1) - Ratio `("T"_1 - "T"_2)/"P"_"cond"` is called as thermal resistance (RT) of material.
- The SI unit of thermal resistance is °C s/ kcal or °C s/J and its dimensional formula is [L–2 M–1T3K1].
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