Heat transfer through the walls can be considered as steady under the assumption that the highest temperature setting for the oven, and the stane room temperature for the ambient. True or False True False

Which of the following are correct and valid for the Kelvin-Plank statement? O a. Any device O b. Kelvin- Planck O c. It is possible for any O d. No heat engine can have a thermal O e. Kelvin- Planck O f. It is impossible O g. It is impossible for any device O h. It is impossible that statement statement to construct to construct of the second law is device that a device that a device that violates of the efficiency of 100 second law is the that operates in a cycle and produces no effect other than Kelvin- operates in a cycle and produces no effect other than operates negative statement, and a operates on a cycle to receive heat from a single reservoir Planck percent, or as for a positive statement, and a positive on a cycle to receive heat statement power plant to operate, the working fluid also violates negative statement the from a statement the transfer the transfer single reservoir and Clausius cannot be can be of heat from and of heat from a lower- temperature body to a higher-…

On a windy day, a camper feels colder as compared to a day at the same temperature when there is no wind. Which of the following heat transfer mechanisms explains this result?   a. Convection   b. Radiation   c. None of the above   d. All of the above   e. Conduction

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 TAs = 200°C a. 9.0 W/ °C b. 5.5 W/ °C C. 6.0 W/ °C d. 16 W/ °C a. 0.672 b. 0.232 C. 0.0672 d. 0.023289 a. 250 W/mK b. 1.25 W/mK 6 cm C. 0.25 W/mK d. 0.125 W/mK A B с 2 cm 2.5 cm 3 cm g. 47.14% h. 14.14% 3 cm 2. The heat transfer due to radiation from a surface of 2 cm² area at 800 °C to a very cold enclosure is 5.0 W. Determine the emissivity of the surface at this temperature D 4 cm Problem 1.34 6 cm 3. An electric wire carrying current is covered with an insulating material. The critical diameter of the insulation is 10 mm. The outside air has heat transfer coefficient of 25 W/m² K TDs = 50°C 4. A hot potato is put in water bowl. Another hot potato of same temperature and size is kept in open air at same temperature that of water. Which potato will cool quicker and why? a. Potato in water bowl, as there will high convection comparatively b.…