2. (10 pts) Consider an incandescent bulb as shown in the figure that consists of a...

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2. (10 pts) Consider an incandescent bulb as shown in the figure that consists of a tungsten filament enclosed in an evacuated glass bulb. The bulb is located in a room with an ambient air and a convective heat transfer coefficient of h W/mK. The emissivity of the filament is & and that of the glass bulb surface is b. Consider a transient process wherein the bulb is turned on and filament generates energy. Write the pertinent simplified form of the energy balance using given symbolic values in the figure as it applies to, i. The control volume that encloses the filament ii. The control surface that encloses the glass bulb surface Denote properties using conventional symbols and, use b and f subscripts to specify properties of bulb and filament respectively. Troom Bulb control surface Evacuated enclosure T-, h T- Filament control volume 2. (10 pts) Consider an incandescent bulb as shown in the figure that consists of a tungsten filament enclosed in an evacuated glass bulb. The bulb is located in a room with an ambient air and a convective heat transfer coefficient of h W/mK. The emissivity of the filament is & and that of the glass bulb surface is b. Consider a transient process wherein the bulb is turned on and filament generates energy. Write the pertinent simplified form of the energy balance using given symbolic values in the figure as it applies to, i. The control volume that encloses the filament ii. The control surface that encloses the glass bulb surface Denote properties using conventional symbols and, use b and f subscripts to specify properties of bulb and filament respectively. Troom Bulb control surface Evacuated enclosure T-, h T- Filament control volume