Harmonic mean temperature difference is given by_________________?
Correct answer: B. 2 (ΔT1 . ΔT2)/(ΔT1 + ΔT2)
- A. √(ΔT1 . ΔT2)
- B. 2 (ΔT1 . ΔT2)/(ΔT1 + ΔT2)
- C. 2 (ΔT1 . ΔT2)/(ΔT1 - ΔT2)
- D. (ΔT1 - ΔT2)/(ΔT1 . ΔT2)
Explanation
The harmonic mean of two temperature differences is twice their product divided by their sum. Therefore, ΔT_h = 2ΔT1ΔT2/(ΔT1+ΔT2).
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