- #1
toothpaste666
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Homework Statement
The temperature within the Earth's crust increases about 1.0 C∘ for each 30 m of depth. The thermal conductivity of the crust is 0.80 W/C∘⋅m.
A)Determine the heat transferred from the interior to the surface for the entire Earth in 9.0h .
B)Compare this heat to the amount of energy incident on the Earth in 9.0h due to radiation from the Sun.
Homework Equations
dQ/dt = kA(dT/l)
The Attempt at a Solution
I have solved the first part.
surface area of Earth = 4pir^2 = 4pi(6.378x10^6 m)^2 = 5.1x10^14 m^2
dQ/dt = kA(dT/l)
dQ/dt = (.80 J/smC)(5.1x 10^14 m^2)(1 C/ 30m)
dQ/dt = 1.36x10^13 J/s
9h is 9h(3600 s/h) = 32400 s
32400s(1.36x10^13 J/s) = 4.4x10^17 J
The second part I am having a hard time understanding. I'm not really sure I even know what they are asking