Heat transfer co-efficient equation for forced convection Nu = 0 023...

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Heat transfer co-efficient equation for forced convection, Nu = 0.023 R_e^0.8 . P_rⁿ, is not valid, if the value of

A. N = 0.4 is used for heating

B. N = 0.3 is used for cooling

C. Reynolds number for the flow involved is > 10000

D. Reynolds number for the flow involved is < 2100

Answer: Option D

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