Questions and answers for exam Preparation

MCQs

Total Questions : 2525 | Page 249 of 253 pages

Question 2481. Log mean temperature difference (LMTD) cannot be used, if ___________________?

Heat transfer co-efficient over the entire heat exchanger is not constant
There exists an unsteady state
The heat capacity is not constant and there is a phase change
None of these

Discuss Question

Answer: Option D. -> None of these
NO EXPLANATION IS AVAILABLE FOR THIS QUESTION!

Question 2482. _____________ paint has the minimum absorption co-efficient?

Black
White lead
Grey
Light cream

Discuss Question

Answer: Option B. -> White lead
NO EXPLANATION IS AVAILABLE FOR THIS QUESTION!

Question 2483. Duhring‟s rule is important in solving problems on__________________?

Distillation
Crystallisation
Evaporation
Humidification

Discuss Question

Answer: Option C. -> Evaporation
NO EXPLANATION IS AVAILABLE FOR THIS QUESTION!

Question 2484. The film thickness for laminar film condensation on vertical surface _____________ from top to bottom?

Cumulatively increases
Cumulatively decreases
Remain constant
And the surface conductance increase

Discuss Question

Answer: Option A. -> Cumulatively increases
NO EXPLANATION IS AVAILABLE FOR THIS QUESTION!

Question 2485. Heat transfer by radiation between two bodies at T1 & T2 and in an ambient temperature of Ta°C depends on_____________?

T1 – T2
T1 – Ta
T2 – Ta
None of these

Discuss Question

Answer: Option D. -> None of these
NO EXPLANATION IS AVAILABLE FOR THIS QUESTION!

Question 2486. Baffles in the shell side of a shell and tube heat exchanger ?

Increase the cross-section of the shell side liquid
Force the liquid to flow parallel to the bank
Increase the shell side heat transfer co-efficient
Decrease the shell side heat transfer co-efficient

Discuss Question

Answer: Option C. -> Increase the shell side heat transfer co-efficient
NO EXPLANATION IS AVAILABLE FOR THIS QUESTION!

Question 2487. What is the steam economy in case of a single effect evaporator system ?

Discuss Question

Answer: Option C. -> < 1
NO EXPLANATION IS AVAILABLE FOR THIS QUESTION!

Question 2488. Which of the following is concerned with both heat and mass transfer ?

Lewis relationship
Nusselt number
Kutateladze number
Froude number

Discuss Question

Answer: Option A. -> Lewis relationship
NO EXPLANATION IS AVAILABLE FOR THIS QUESTION!

Question 2489. Controlling heat transfer film co-efficient is the one, which offers ______________ resistance to heat transfer?

No
The least
The largest
Lower

Discuss Question

Answer: Option C. -> The largest
NO EXPLANATION IS AVAILABLE FOR THIS QUESTION!

Question 2490. For turbulent flow in a tube, the heat transfer co-efficient is obtained from the Dittus- Boelter correlation. If the tube diameter is halved and the flow rate is doubled, then the heat transfer co-efficient will change by a factor of________________?