Heat Transfer Problem: Finding Temperature Difference in Insulated System

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Homework Statement


Two bodies of masses [itex]m[/itex][itex]_{1}[/itex] and [itex]m[/itex][itex]_{2}[/itex] and specific heat capacities [itex]s[/itex][itex]_{1}[/itex] and [itex]s[/itex][itex]_{2}[/itex] , are connected by a rod of length [itex]l[/itex] and cross-sectional area [itex]A[/itex], thermal conductivity [itex]K[/itex] and negligible heat capacity. The whole system is thermally insulated. At time [itex]t=0[/itex], the temperature of the first body is [itex]T[/itex][itex]_{1}[/itex] and the temperature of the second body is [itex]T[/itex][itex]_{2}[/itex] ([itex]T[/itex][itex]_{2}[/itex] [itex]>[/itex] [itex]T[/itex][itex]_{1}[/itex] ). Find the temperature difference between the bodies at time [itex]t[/itex].

Homework Equations


[itex]dQ/dt = KAdT/dx[/itex]

[itex]dQ = msdθ[/itex]


The Attempt at a Solution


I was able to set up [itex]2[/itex] equations relating the amount of heat transferred through the rod in a time [itex]dt[/itex] to the rise and fall of temperatures of the masses [itex]m[/itex][itex]_{2}[/itex] and [itex]m[/itex][itex]_{1}[/itex] respectively. I don't know how to proceed after this ?
 
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Since the heat capacity of the rod is neglected, the temperature profile in the rod is linear:

dT/dx = (T2-T1)/l

You need to write your second equation twice: once for m1 and once for m2.
Then you can simply solve the equations.