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## Homework Statement

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I have two spherical metallic shells with radius ##3a## and ##a##, the little one is placed inside the larger so that the center of the little one is at a distance of ##a## from the center of the larger. The outer one has a charge ##3Q## and the one inside has a charge of ##Q## (both are positive).

Now if we are grounding the outher shell with a thread that has a resistance R some energy will be released as heat, calculate the heat!

## Homework Equations

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This is the problem

## The Attempt at a Solution

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The problem is 15 years old and in the solution they are referring to some litterature that we dont use today so I got the answer itself but no solution to follow.

This is my thoughts so far:

When we set this configuration up we are storing some energy in the electric field. This energi can be calculated as

##

W = \frac{\epsilon_0}{2} \int_{

{\rm I\!R}^3} ( E_1^2 + E_2^2 + 2\textbf{E}_1 \cdot \textbf{E}_2 ) dV

##

and when we are grounding the outher shell, all of these should be released somehow, isn't it all heat then? Is the ##R## only there to confuse me?