The overall resistance for heat transfer through a series of flat resistance, is the __________ of the resistances. (A) Average (B) Geometric mean (C) Product (D) Sum

The overall resistance for heat transfer through a series of flat
resistance, is the __________ of the resistances.
(A) Average
(B) Geometric mean
(C) Product
(D) Sum
by

1 Answer

Answer :

(D) Sum
by

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In case of heat transfer by conduction in a hollow cylinder, __________ mean area is used to calculate the heat transfer rate. (A) Geometric (B) Arithmetic (C) Logarithmic (D) Either (A), (B) or (C)

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In case of vertical tube evaporator, with increase in liquor level, the overall heat transfer co-efficient (A) Increases (B) Decreases (C) Is not affected (D) May increase or decrease; depends on the feed

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