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Thermal Diffusion Equation :(

By dimensional analysis of the thermal diffusion equation,

Tt=kΔ2T\displaystyle \frac{\partial T}{\partial t} =k\Delta^2T

(T is temperature, k is the thermal diffusivity depending on the material properties of the medium)

show that the thermal diffusion time is giving by

τ=L2/k\tau = L^2/k

Any help really appreciated
Reply 1
Nobody?
Have a think about the units (particularly what del squared is, writing it out more explicitly might help). The "rearrange" to get time on one side, and everything else on the other (nb this is not solving it in any way) - anything with the same units you can cancel (eg you have temperature on both sides...). See what you get left with, and that's your answer (quite difficult to type help, sorry!)

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