67 10 1 800 500 1026 W/M 10.26 KW/MQ= × − × ×23 − = =IES-52. ANS. (D...
5.67 10
1
800
500
1026 W/m
10.26 kW/m
Q
=
×
−
× ×
23
−
=
=
IES-52. Ans. (d)
IES-53. Ans. (c)
J
=
ε
E
b
+
(
1
−
ε
)
G
12
= ×
ε
10
+
(
1
−
ε
)
×
20 or
ε
=
0.8
IES-54. Ans. (b)
IES-55. Ans. (c)
IES-56. Ans. (a) The resistance due to steam film and pipe material are negligible in
comparison to resistance of insulation material and resistance due to air film.
IES-57. Ans. (a) All resistances are in series.
IES-58. Ans. (b) 1. In conduction, heat resistance =
Δ
x/kA
Thus reduction in thickness and increase in area result in reduction of thermal
resistance.