1. The thermal resistance of A, B, C, and D are 1, 2, 2, 4 W/ °C, respectively. The totalthermal resistance to the wall conductance will beTAs = 200°Ca. 9.0 W/ °Cb. 5.5 W/ °CC. 6.0 W/ °Cd. 16 W/ °Ca. 0.672b. 0.232C. 0.0672d. 0.023289a. 250 W/mKb. 1.25 W/mK6 cmC. 0.25 W/mKd. 0.125 W/mKABс2 cm 2.5 cm3 cmg. 47.14%h. 14.14%3 cm2. The heat transfer due to radiation from a surface of 2 cm² area at 800 °C to a very coldenclosure is 5.0 W. Determine the emissivity of the surface at this temperatureD4 cmProblem 1.346 cm3. An electric wire carrying current is covered with an insulating material. The criticaldiameter of the insulation is 10 mm. The outside air has heat transfer coefficient of 25W/m² KTDs = 50°C4. A hot potato is put in water bowl. Another hot potato of same temperature and size iskept in open air at same temperature that of water. Which potato will cool quicker andwhy?a. Potato in water bowl, as there will high convection comparativelyb. Potato in water bowl, as there will high conduction comparativelyC. Potato in air, as there will high convection comparativelyd. Potato in air, as there will high conduction comparatively5. The values of heat transfer coefficient, diameter of fin and thermal conductivity are25 W/m² K, 0.01 m are 200 W/m K respectively. If the length of the long fin is 0.3 m,then efficiency of the fin will bee. 100%f. 74.14%

Answered: Image /qna-images/answer/ff7f923a-397b-48d9-bf55-5f1eaa04d4b0.jpg

1. The thermal resistance of A, B, C, and D are 1, 2, 2, 4 W/ °C, respectively. The total thermal resistance to the wall conductance will be TA - 200°C a. 9.0 W/ °C b. 5.5 W/ °C C. 6.0 W/ °C d. 16 W/°C 6 cm A B It 2 cm 2.5 cm + 3 cm D 4 cm Problem 1.34 Tp. = 50°C

1. The thermal resistance of A, B, C, and D are 1, 2, 2, 4 W/ °C, respectively. The total thermal resistance to the wall conductance will be TA - 200°C a. 9.0 W/ °C b. 5.5 W/ °C C. 6.0 W/ °C d. 16 W/°C 6 cm A B It 2 cm 2.5 cm + 3 cm D 4 cm Problem 1.34 Tp. = 50°C

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.21P

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