If h1 = inner film co-efficient and h2 = outer film co-efficient, then – McqOptions

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1.	If h1 = inner film co-efficient and h2 = outer film co-efficient, then the overall heat transfer co-efficient is
A.	always less than h1
B.	always between h1 and h2
C.	always higher than h2
D.	dependent on metal resistance
Answer» C. always higher than h2

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