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Que. Heat is transferred from a hot fluid to a cold one through a plane wall of thickness (δ), surface area (A) and thermal conductivity (k). The thermal resistance is
a. 1/A (1/h₁ + δ/k + 1/h₂)
b. A (1/h₁ + δ/k + 1/h₂)
c. 1/A (h₁ + δ/k + h₂)
d. A (1/h₁ + δ/k + 1/h₂)
Correct Answer:1/A (1/h₁ + δ/k + 1/h₂)
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