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Problem 2. A long thin alloy wire with a diameter of 0.2 mm is exposed to ambient air at T, -25°C with a combined heat transfer coefficient h-10 W/m2.K (due to natural convection and radiation). An electric current10.15 A flows through the wire. The electrical resistance of the wire per unit length is R-162/m. (a) Draw a control volume to write down the energy balance equation. (b) Determine the steady-state temperature of the alloy wire, assuming that the solid wire is at a uniform temperature Tw. (c) Plot the steady state temperature Tw as a function of the heat transfer coefficient h, which is allowed to vary between 5 and 45 W/m-.K, consider three values of the resistance per length: R-10, 16, and 20 Ω/m. The other conditions remain the same.

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