# HELP: Conservation of EnergyWatch

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#1
Seeking help here I'm revising for my Continua finals this friday, and I am extremely weak in this area.... Encountered this Conservation of Energy problem and I hope someone may be able to help me before doomsday this Friday
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A small block of rubber, dimensions L1, L2 and L3, is sandwiched between two electrodes. This rubber is subjected to external forces F1, F2 and F3 and a voltage V. See figure below.

The forces produce displacements d1, d2, d3 respectively, and charge Q is deposited on the electrodes due to the voltage.

The total energy density in the rubber may be written as a function
$W=\left ( \varepsilon 1,\varepsilon 2,\varepsilon 3, D \right )$,
where $\varepsilon 1=\frac{d1}{L1}, \varepsilon 2=\frac{d2}{L2},\varepsilon 3=\frac{d3}{L3}, D=\frac{Q}{L1\times L2}$.

Assuming the thermal energy remains constant, what is the energy balance equation for this system?

What is the relationship between F1, F2, F3, V and the energy density W?

Given that $W=\frac{k}{2} [ \left ((\varepsilon 1)+1 \right )^{2}+ ((\varepsilon 2)+1 )^{2}+((\varepsilon 3)+1) \right )^{2}-3 ]+\frac{D^{2}}{2\beta }((\varepsilon 3)+1)^{2}$
where k and $\beta$ are constants,
obtain explicit relations between the work conjugates.
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I'm overwhelmed by the question!!! Help me please!
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