A picture window has dimensions of 1.40 m×m×2.50 mm and is made of glass 5.80 mm thick. On a winter day, the outside temperature is -16.0 ∘C∘C , while the inside temperature is a comfortable 20.5∘C. while the inside temperature is comfortable 19.5 degree C.

a. At what rate is heat being lost through the window by conduction?
b. At what rate would heat be lost through the window if you covered it with a 0.750 mm thick layer of paper ( thermal conductivity 0.0500 W/m. K).

a.

b.

Explanation:

a.Given

#To calculate the rate at which heat is being lost by conduction, we first calculate thermal resistance:

#The rate of heat loss can be determined from the equation:

=

Hence, the rate of heat loss through the window by conduction is

b.Given that thermal conductivity is 0.0500W/m.K and

#After covering the window with the paper, there will be additional thermal resistance:

#To calculate the rate of heat loss if window is covered,

#The rate of heat loss when the window is covered is