MCQs / Q&A

Out of the following four assumptions used in the derivation of the equation for LMTD [LMTD = (Δt1 – Δt2)/ln(Δt1/Δt2)], which one is subject to the largest deviation in practice ?

by
Out of the following four assumptions used in the derivation of the equation for LMTD [LMTD = (Δt1 – Δt2)/ln(Δt1/Δt2)], which one is subject to the largest deviation in practice ?

A. Constant overall heat transfer co-efficient.
B. Constant rate of fluid flow (Correct)
C. Constant specific heat
D. No partial phase change in the system

 

Pick out the wrong statement?

by
Pick out the wrong statement?

A. Metal/alloys having hexagonal crystal lattice structure are less malleable than those having
cubic crystal lattice structure
B. Metal/alloys having body centred cubic (bcc) crystal lattice structure is stronger & less ductile
than those having face centred cubic (fcc) crystal lattice structure
C. Tungsten has a body centred cubic (bcc) crystal lattice structure (Correct)
D. Both ferritic & austenitic stainless steel has a face centred cubic (fcc) crystal structure

 

Bacterial aerobic oxidation of polluted water in biological oxidation ponds is done to purify it. Presence of bacteria helps in____________________?

by
Bacterial aerobic oxidation of polluted water in biological oxidation ponds is done to purify it. Presence of bacteria helps in____________________?

A. Coagulation and flocculation of colloids
B. Oxidation of carbonaceous matter to CO2
C. Nitrification or oxidation of ammonia derived from breakdown of nitrogenous organic matter
to the nitrite and eventually to the nitrate
D. All A., B. and C. (Correct)