Network Approach MCQs : This section focuses on the "Network Approach". These Multiple Choice Questions (MCQs) should be practiced to improve the Network Approach skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Question 1
A ring (E = 0.85) of 8 cm inner and 16 cm outer diameter is placed in a horizontal plane. A small element (E = 0.7) of 1 cm2 is placed concentrically 8 cm vertically below the center of the ring. The temperature of the ring is 800 K and that of small area is 400 K. Find the radiant heat gain by the small ring
A. - 10.59 J/hour
B. - 11.59 J/hour
C. - 12.59 J/hour
D. - 13.59 J/hour
Question 2
Consider the above problem, if temperature difference is doubled by raising the temperature 480 K to 540 K, then how this heat flux will be affected?
A. 1803.55 W/m2
B. 1703.55 W/m2
C. 1603.55 W/m2
D. 1503.55 W/m2
Question 3
Determine the radiant heat flux between two closely spaced, black parallel plates radiating only to each other if their temperatures are 850 K and 425 K. The plates have an area of 4 m2
A. 0.04
B. 0.03
C. 0.02
D. 0.01
Question 4
The net rate at which the radiation leaves the surface is given by
A. e (E b – J)/1 – 4 e
B. e (E b – J)/1 – 3 e
C. e (E b – J)/1 – 2 e
D. e (E b – J)/1 – e
Question 5
The total radiant energy incident upon a surface per unit time per unit area is known as
A. Shape factor
B. Radiosity
C. Radiation
D. Irradiation
Question 6
The total radiant energy leaving a surface per unit time per unit surface area is represented by
A. Radiation
B. Radiosity
C. Irradiation
D. Interchange factor
Question 7
Two opposed, parallel, infinite planes are maintained at 420 K and 480 K. Calculate the net heat flux between these planes if one has an emissivity of 0.8 and other an emissivity of 0.7
A. 534.86 W/m2
B. 634.86 W/m2
C. 734.86 W/m2
D. 834.86 W/m2
Question 8
What is the value of grey body factor for concentric cylinders?
A. 3/ [1 – e 1/e 1 + 1 + 1 – e 2/e 2 (A 1/A 2)].
B. 4/ [1 – e 1/e 1 + 1 + 1 – e 2/e 2 (A 1/A 2)].
C. 1/ [1 – e 1/e 1 + 1 + 1 – e 2/e 2 (A 1/A 2)].
D. 2/ [1 – e 1/e 1 + 1 + 1 – e 2/e 2 (A 1/A 2)].
Question 9
Which one of the following is true for the opaque non-black surface?
A. J = E +2 p G
B. J = E + p G
C. J = 2 E + p G
D. J = ½ E + p G
Question 10
A ring (E = 0.85) of 8 cm inner and 16 cm outer diameter is placed in a horizontal plane. A small element (E = 0.7) of 1 cm2 is placed concentrically 8 cm vertically below the center of the ring. The temperature of the ring is 800 K and that of small area is 400 K. Find the radiant heat gain by the small ring
A. – 10.59 J/hour
B. – 11.59 J/hour
C. – 12.59 J/hour
D. – 13.59 J/hour