Question

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: (b).always between h1 and h2

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Q. If h1 = inner film co-efficient and h2 = outer film co-efficient, then the overall heat transfer co-efficient is

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