Pick out the correct statement.
(A) Fanning friction factor is inversely proportional to Reynolds number
always
(B) The property of a randomly packed bed (with raschig rings) is given by
the ratio of the total volume to the volume of voids in the bed
(C) Mach number in an incompressible fluid is always unity
(D) Mach number is given by the ratio of the speed of the fluid to that of
sound in the fluid under conditions of flow

1 Answer

Answer :

(D) Mach number is given by the ratio of the speed of the fluid to that of
sound in the fluid under conditions of flow

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