Question
Find the relation between the equilibrium radius $r$, the potential $\phi$, and the excess of ambient pressure over internal pressure $\Delta p$ of a charged soap bubble, assuming that surface tension can be neglected.
Step 1
The bubble has an internal pressure \( p_{\text{in}} \) and an external ambient pressure \( p_{\text{out}} \). The excess of ambient pressure over internal pressure is defined as \( \Delta p = p_{\text{out}} - p_{\text{in}} \). Show more…
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