Download PDF
Free download in PDF Heat Transfer Multiple Choice Questions with Answers for competitive exams. These short objective type questions with answers are very important for competitive exams like IIT-JEE, AIIMS, NEET etc. as well as Board exams. These short solved questions or quizzes are provided by Gkseries.
61
Total emissivity of polished silver compared to black body is
[A]
Same
[B]
Higher
[C]
More Or Less Same
[D]
Very Much Lower
62
Stefan Boltzmann law is applicable for heat transfer by
[A]
conduction
[B]
convection
[C]
radiation
[D]
conduction and radiation combined
63
The thermal diffusivities for solids are generally
[A]
less than those for gases
[B]
jess than those for liquids
[C]
more than those for liquids and gases
[D]
more or less same as for liquids and gases
Answer: more than those for liquids and gases
64
According to Stefan’s law, the total radiation from a black body per second per unit area is proportional to
[A]
absolute temperature
[B]
T2
[C]
T5
[D]
t
65
The total emissivity power is .defined as the total amount of radiation emitted by a black body per unit
[A]
Temperature
[B]
Thickness
[C]
Area
[D]
Time
66
The ratio of the energy absorbed by the body to total energy falling on it is called
[A]
Absorptive Power
[B]
Emissive Power
[C]
Absorptivity
[D]
Emissivity
67
The amount of radiation mainly depends on
[A]
nature of body
[B]
temperature of body
[C]
type of surface of body
[D]
All Of The Above
68
The emissive power of a body depends upon its
[A]
Temperature
[B]
Wave Length
[C]
Physical Nature
[D]
All Of The Above
69
In regenerator type heat exchanger, heat transfer takes place by
[A]
direct mixing of hot and cold fluids
[B]
a complete separation between hot and cold fluids
[C]
flow of hot and cold fluids alternately over a surface
[D]
generation of heat again and again
Answer: flow of hot and cold fluids alternately over a surface
70
If the temperature of a solid surface changes form 27°C to 627°C, then its emissive power changes in the ratio of
Please share this page