A picture window has dimensions of 1.40 m x p m and is made of glass 5.20 mm thick. On a winter day, the outside temperature is -20 &nbsp;while the inside temperature is a comfortable 19.56 °C. If the rate of &nbsp;heat &nbsp;loss through the window is 5.7 x &nbsp;J/sFind the value of p &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;(3 marks)How much heat flows through the window in one hour? &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; (3 marks)

Question

A picture window has dimensions of 1.40 m x p m and is made of glass 5.20 mm thick. On a winter day, the outside temperature is -20 &amp;nbsp;while the inside temperature is a comfortable 19.56 °C. If the rate of &amp;nbsp;heat &amp;nbsp;loss through the window is 5.7 x &amp;nbsp;J/sFind the value of p &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp;(3 marks)How much heat flows through the window in one hour? &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp; (3 marks)

madeleinejames20 · Accepted Answer

To solve this problem, we need to use the formula for heat transfer through a window. The formula is given by:Q=k·A·ΔTdwhere:- Q is the heat transfer (in joules)- k is the thermal conductivity of the glass (in joules per second per meter per degree Celsius)- A is the area of the window (in square meters)- ΔT is the temperature difference between the inside and outside of the window (in degrees Celsius)- d is the thickness of the glass (in meters)(a) Finding the value of p:In this part, we are given the heat loss rate (Q) as 5.7 J/s. We can substitute the given values into the formula and solve for p.Q=k·A·ΔTd5.7=k·(1.40·p)·(-20−19.56)5.20×10−3Simplifying:5.7=k·(1.40p)·(−39.56)5.20×10−3To find the value of p, we need the value of k (thermal conductivity of the glass). Unfortunately, the value of k is not provided in the problem statement. Without the value of k, we cannot solve for p.(b) Heat flow through the window in one hour:To find the heat flow through the window in one hour, we need to multiply the heat transfer rate (Q) by the time in seconds. Since there are 3600 seconds in one hour, we can calculate the heat flow as follows:Heat flow = Q x timeHeat flow = 5.7 J/s x 3600 sHeat flow = 20520 JTherefore, the heat flow through the window in one hour is 20520 joules.

A picture window has dimensions of 1.40 m

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