#6. My buddy is starting to get hypothermic (body temperature 306 K) during an epic backcountry ski adventure. Since I'm quite warm (body temperature 310 K), I decide to get in a sleeping bag with him to try and warm him up. What heat transfer mechanism will be most responsible for heating him up? For simplicity, ignore any internal temperature differences across my body (that is, assume my skin temperature is also 310 K). Use num- bers to support your answer (for human skin, you can use the following values: surface area A = 1.50 m², emissivity € = 0.970, thickness d = 0.0250 m, thermal conductivty 0.200 ms.K

#6. My buddy is starting to get hypothermic (body temperature 306 K) during an epic backcountry ski adventure. Since I'm quite warm (body temperature 310 K), I decide to get in a sleeping bag with him to try and warm him up. What heat transfer mechanism will be most responsible for heating him up? For simplicity, ignore any internal temperature differences across my body (that is, assume my skin temperature is also 310 K). Use num- bers to support your answer (for human skin, you can use the following values: surface area A = 1.50 m², emissivity € = 0.970, thickness d = 0.0250 m, thermal conductivty 0.200 ms.K

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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#6. My buddy is starting to get hypothermic (body temperature 306 K) during an epic backcountry ski adventure. Since I'm quite warm (body temperature 310 K), I decide to get in a sleeping bag with him to try and warm him up. What heat transfer mechanism will be most responsible for heating him up? For simplicity, ignore any internal temperature differences across my body (that is, assume my skin temperature is also 310 K). Use num- bers to support your answer (for human skin, you can use the following values: surface area A = 1.50 m², emissivity = 0.970, thickness d= 0.0250 m, thermal conductivty 0.200 ms.K)
Problem 11: A mass m = 125 kg of lava at TH = 1155° C emerges from a volcano deep in the ocean. At this depth, the ocean water is at a temperature of TC = 2.1° C, and the lava cools and solidifies.The specific heat capacity of the lava for this process is c = 840 J/kg⋅°C and the latent heat of fusion of the lava is Lf = 4.0 × 105 J/kg.Assume that the temperature of the ocean does not change in this process. Part (a) The lava cools to 700.0° C before solidifying. What is the change in entropy ΔS1 of the lava in joules per kelvin during this process? Part (b) Calculate the change in entropy of the ocean waters ΔS2 in joules per kelvin during the cooling of the molten lava. Part (c) Calculate the change in entropy of the lava ΔS3 in joules per kelvin when it solidifies. Part (d) Calculate the entropy change of the ocean ΔS4 in joules per kelvin due to the solidification of the lava.
A solid concrete wall has dimensions 4.0 m × 2.4 m and is 30 cm thick. The thermal conductivity of the concrete is 1.3 W/m ∙ K, and it separates a basement from the ground outside. The inner surface of the wall is at 18°C, and the outside surface is at 6°C. How much heat flows through the wall every hour?
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Equal masses of substance A at 98.1°C and substance B at 26.2°C are placed in a well-insulated container of negligible mass and allowed to come to equilibrium. If the equilibrium temperature is 77.4°C, which substance has the larger specific heat? a) substance A b) The answer depends on the exact initial temperatures. c) More information is required. d) The specific heats are identical.
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