6. The ventilating fan of the bathroom of a building has a volume flow rate of 30 L/s and runscontinuously. The building is located in San Francisco, California, where the average wintertemperature is 12.2 °C, and is maintained at 22°C at all times. The building is heated byelectricity whose unit cost is $0.09/kWh. Determine the amount and cost of the heat "ventedout" per month in winter. (The gas constant and specific heat of air are R 0.287 kJ/kg-K andCp1.0 kl/kg-K. Consider air at P 1 atm. and T-22 °C)12.2°C30 L/s22°CFanBathroom

Answered: 6. The ventilating fan of the bathroom…

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.4P

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Heat is transferred at a rate of 0.1 kW through glass wool insulation (density=100kg/m3) with a 5-cm thickness and 2-m2 area. If the hot surface is at 70C, determine the temperature of the cooler surface.
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