The radiation heat flux from a heating element at a temperature of 800°C, in a furnace maintained at 300°C is 8 kW/m2. The flux, when the element temperature is increased to 1000°C for the same furnace temperature is

The radiation heat flux from a heating element at a temperature of 800°C, in a furnace maintained at 300°C is 8 kW/m<sup>2</sup>. The flux, when the element temperature is increased to 1000°C for the same furnace temperature is

A large plane, perfectly insulated on one face and maintained at a fixed temperature T 1 on the bare face, has an emissivity of 0.84 and loses 250 W/m2 when exposed to surroundings at nearly 0 K. The radiant heat loss from another plane of the same size is 125 W/m2 when bare face having emissivity 0.42 and is maintained at temperature T 2 is exposed to the same surroundings. Subsequently these two planes are brought together so that the parallel bare faces lie only 1 cm apart and the heat supply to each is so regulated that their respective temperatures T 1 and T 2 remains unchanged. Determine he net heat flux between the planes

A

0

B

1

C

2

D

3

Which one of the following four addresses is NOT EXACTLY the same as the one given below? United States Canoe and Kayak Team E-Mail: [email protected] Indianapolis, Indiana (317) 2375690 (800) 7334976 (i) United States Canoe and Kayak Team E-Mail: [email protected] Indianapolis, Indiana (317) 2375690 (800) 7334976 (ii) United States Canoe and Kayak Team E-Mail: [email protected] Indianapolis, Indiana (317) 2375690 (800) 7334976 (iii) United States Canoe and Kayak Team E-Mail: [email protected] Indianapolis, Indiana (317) 2375690 (800) 7334976 (iv) United States Canoe and Kayak Team E-Mail: [email protected] Indianapolis, Indiana (317) 2375690 (800) 7334976

A

i

B

ii

C

iii

D

iv

Which one of the following four addresses is NOT EXACTLY the same as the one given below? Zoar Outdoor E - Mail: [email protected] Mohawk Trail Charlemont, Massachusetts 01339 (800) 5327483 (i) Zoar Outdoor E - Mail: [email protected] Mohawk Trail Charlemont, Massachusetts 01339 (800) 5327483 (ii) Zoar Outdoor E - Mail: [email protected] Mohawk Trail Charlemont, Massachusetts 01339 (800) 5327483 (iii) Zoar Outdoor E - Mail: [email protected] Mohawk Trail Charilemont, Massachasetts 01339 (800) 5327483 (iv) Zoar Outdoor E - Mail: [email protected] Mohawk Trail Charlemont, Massachusetts 01339 (800) 5327483

A

i

B

ii

C

iii

D

iv

Which one of the following four addresses is NOT EXACTLY the same as the one given below? United States Canoe and Kayak Team E - Mail: [email protected] Indianapolis, Indiana (317) 2375690 (800) 7334976 (i) United States Canoe and Kayak Team E - Mail: [email protected] Indianapolis, Indiana (317) 2375690 (800) 7334976 (ii) United States Canoe and Kayak Team E - Mail: [email protected] Indianapolis, Indiana (317) 2375690 (800) 7334976 (iii) United States Canoe and Kayak Team E - Mail: [email protected] Indianapolis, Indiana (317) 2375690 (800) 7334976 (iv) United States Canoe and Kayak Team E - Mail: [email protected] Indianapolis, Indiana (317) 2375690 (800) 7334976

A

i

B

ii

C

iii

D

iv

The bypass factor (B. P. F.) in case of sensible heating of air is (Where td₁ = Dry bulb temperature of air entering the heating coil, td₂ = Dry bulb temperature of air leaving the heating coil, and td₃ = Dry bulb temperature of heating coil)

A

(td₂ - td₃)/(td₃ - td₁)

B

(td₃ - td₂)/(td₃ - td₁)

C

(td₃ - td₁)/(td₂ - td₃)

D

(td₃ - td₁)/(td₃ - td₂)

The bypass factor (B.P.F.) in case of sensible heating of air is (Where td₁ = Dry bulb temperature of air entering the heating coil, td₂ = Dry bulb temperature of air leaving the heating coil and td₃ = Dry bulb temperature of heating coil)

A

$$\frac{{{\text{t}}{{\text{d}}_2} - {\text{t}}{{\text{d}}_3}}}{{{\text{t}}{{\text{d}}_3} - {\text{t}}{{\text{d}}_1}}}$$

B

$$\frac{{{\text{t}}{{\text{d}}_3} - {\text{t}}{{\text{d}}_2}}}{{{\text{t}}{{\text{d}}_3} - {\text{t}}{{\text{d}}_1}}}$$

C

$$\frac{{{\text{t}}{{\text{d}}_3} - {\text{t}}{{\text{d}}_1}}}{{{\text{t}}{{\text{d}}_2} - {\text{t}}{{\text{d}}_3}}}$$

D

$$\frac{{{\text{t}}{{\text{d}}_3} - {\text{t}}{{\text{d}}_1}}}{{{\text{t}}{{\text{d}}_3} - {\text{t}}{{\text{d}}_2}}}$$

The rear window of an automobile is made of thick glass i.e. AB = 5 mm and thermal conductivity is 0.8 W/m degree. To defrost this window, a thin transparent film type heating element has been fixed to its inner surface. For the conditions given below, determine the electric power that must be provided per unit area of window if a temperature 5 degree Celsius is maintained at its outer surface. Interior air temperature and the corresponding surface coefficient are 20 degree Celsius and 12 W/m2 degree. Surrounding air temperature and the corresponding surface coefficient are – 15 degree Celsius and 70 W/m2 degree. Electric heater provides uniform heat flux

A

232.5 /m2

B

1232.5 /m2

C

2232.5 /m2

D

3232.5 /m2

A Carnot heat engine receives heat at 750 K and rejects the waste heat to the environment at 300 K. The net work output of the heat engine is used to drive a Carnot refrigerator, whose COP is 6.14. If the heat removal rate from the refrigerated space is 6.6 kW, determine the rate of heat supply to the heat engine?

A

2.79 kW

B

1.79 kW

C

4.79 kW

D

7.79 kW

Which one of the following four addresses is EXACTLY same as the given below? Carlos Alfredo P.O. Box 300 Viale delle Caraccalla 00100 Rome, ITALY (i) Carlos Alfredo P.O. Box 300 Viale delle Caracalla 00100 Rome, ITALY (ii) Carlos Alfredo P.O. Box 300 Viale delle Caraccalla 00100 Rome, ITALY (iii) Carlos Alfredo P.O. Box 300 Viale delle Caracalla 00100 Rome, ITALY (iv) Carlos Alfredo P.O. Box 300 Viale delle Caracalla 00100 Rome, ITALY

A

i

B

ii

C

iiii

D

iv

The atmospheric air at dry bulb temperature of 15°C enters a heating coil maintained at 40°C. The air leaves the heating coil at 25°C. The bypass factor of the heating coil is

A

0.376

B

0.4

C

0.6

D

0.67

The radiation heat flux from a heating element at a temperature of 800°C, in a furnace maintained at 300°C is 8 kW/m². The flux, when the element temperature is increased to 1000°C for the same furnace temperature is

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