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3 months ago

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A windowpane is half a centimeter thick and has an area of 1.0 m2. The temperature difference between the inside and outside sur

faces of the pane is 15° C.
What is the rate of heat flow through this window? (Thermal conductivity for glass is 0.84 J/s⋅m⋅°C.)
a. 50 000 J/sb. 2 500 J/sc. 1 300 J/sd. 630 J/s

1 answer:

Keith_Richards [3.2K]3 months ago

3 0

To tackle this problem, one must utilize the ideas related to the rate of heat flux defined in energetic terms. The heat transfer rate signifies the quantity of heat moved per time unit through a specific material. This can be calculated mathematically in the following manner:

$\frac{Q}{t} = \frac{kA}{L} (T_H - T_C)$

Where

k = 0.84 J/s⋅m⋅°C (This is the thermal conductivity of the substance)

$A = 1m^2$ Area

$L = 5*10^{-3}m$ Length

$T_H$ = Temperature of the "hot" reservoir

$T_C$ = Temperature of the "cold" reservoir

Substituting our specific values provides us with,

$\frac{Q}{t} = \frac{kA}{L} (T_H - T_C)$

$\frac{Q}{t} = \frac{(0.84)(1)}{0.005} (15)$

$\frac{Q}{t} = 2520J/s$

Thus, the accurate option is B.

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3 months ago