TOP Heat Transfer - Mechanical Engineering Multiple choice Questions and Answers pdf

11.    Heat transfer in liquid and gases takes place by
(a)     conduction   
(b)     convection
(c)     radiation
(d)    conduction and convection
(e)    convection and radiation.
Ans: b

12.    Which of the following is the case of heat transfer by radiation
(a)    blast furnace
(b)    heating of building
(c)    cooling of parts in furnace
(d)    heat received by a person from fireplace
(e)    all of the above.
Ans: d

13.    Heat is closely related with
(a) liquids
(b) energy
(c) temperature  
(d) entropy
(e) enthalpy.
Ans: c

14.    Pick up tne wrong case. Heat flowing from one side to other depends directly on
(a) face area
(b) time
(c) thickness
(d) temperature difference
(e) thermal conductivity.
Ans: c

15.    Metals are good conductors of heat because
(a)    their atoms collide frequently
(b)    thier atoms-are relatively far apart
(c)    they contain free electrons
(d)    they have high density
(e)    all of the above.
Ans: a

16.     Which of the following is a case of steady state heat transfer
(a) I.C. engine   
(b) air preheaters
(c) heating of building in winter
(d) all of the above
(e) none of the above.
Ans: e

17.    Total heat is the heat required to
(a)    change vapour into liquid
(b)    change liquid into vapour
(c)    increase the temperature of a liquid or vapour
(d)    convert water into steam and superheat it
(e)    convert saturated steam into dry steam.
Ans: d

18.    Cork is a good insulator because it has
(a)    free electrons
(b)    atoms colliding frequency
(c)    low density  
(d)     porous body
(e)     all of the above.
Ans: d

19.    Thermal conductivity of water in general with rise in temperature
(a) increases
(b) decreases
(c) remains constant
(d) may increase or decrease depending on temperature
(e) none of the above.
Ans: d

20.    Thermal conductivity of water at 20°C is of the order of
(a) 0.1
(b) 0.23
(c) 0.42
(d) 0.51
(e) 0.64.
Ans: d

Read More Questions:
Heat Transfer - Mechanical MCQs Part1
Heat Transfer - Mechanical MCQs Part2

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