I need help on this fourniers Law Problem. Assume it is winter and the thermal conductivity of glass k = 0.85 W/m K. (a) Let's say that it is chilly To outside, and a much warmer T; inside. If we were to have a single-pane window(which is made of a single piece of glass) with a thickness w and an area A, write an equation for (i) the fluxof heat Fh across the window; and (ii) the flow of heat Qh across the window. What are the units of F, andQn?(b) Determine values for Fh and Qh assuming that To = -15°C, T¡ = +20°C, w = 7 mm, and A = 0.8 m2.(c) If there are about nw(kWh), estimate the heating bill per month (in US dollars) just to offset losses through the windows? [Andnow you can see why double-paned windows, which are much more insulating, are normal in cold climates!]20 such windows in the house, and energy costs 10 cents (US) per kilowatt-hour

Heat move through a plane mass of thickness x as displayed underneath can be demonstrated as :The…

(a) Let's say that it is chilly To outside, and a much warmer T; inside. If we were to have a single-pane window (which is made of a single piece of glass) with a thickness w and an area A, write an equation for (i) the flux of heat Fh across the window; and (ii) the flow of heat Qh across the window. What are the units of Fh and Qn? (b) Determine values for Fh and Qn assuming that T, = -15°C, T; = +20°C, w =7 mm, and A = 0.8 m². (c) If there are about nw = 20 such windows in the house, and energy costs 10 cents (US) per kilowatt-hour (kWh), estimate the heating bill per month (in US dollars) just to offset losses through the windows? [And now you can see why double-paned windows, which are much more insulating, are normal in cold climates!]

(a) Let's say that it is chilly To outside, and a much warmer T; inside. If we were to have a single-pane window (which is made of a single piece of glass) with a thickness w and an area A, write an equation for (i) the flux of heat Fh across the window; and (ii) the flow of heat Qh across the window. What are the units of Fh and Qn? (b) Determine values for Fh and Qn assuming that T, = -15°C, T; = +20°C, w =7 mm, and A = 0.8 m². (c) If there are about nw = 20 such windows in the house, and energy costs 10 cents (US) per kilowatt-hour (kWh), estimate the heating bill per month (in US dollars) just to offset losses through the windows? [And now you can see why double-paned windows, which are much more insulating, are normal in cold climates!]

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.12P

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