Spherical capacitor RC system -- determine steady state charges

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palaphys
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Homework Statement
Three uncharged metallic balls of radii a, b and a respectively are connected to terminals A, B and C with the help of long thin conductors as shown in the circuit. Find charges established on each of the balls, when a steady state is reached after the switch is closed. Consider the balls to be at great distances from each other as well from the circuit and neglect internal resistance of the battery.
Relevant Equations
Q=CV ,V=iR
1757832369543.webp

This is the diagram given for the problem.
Now I was able to identify, that the fact that the capacitance of a spherical capacitor, with one plate and the other at an infinite distance, is somehow to be used in this problem, i.e ##C= 4\pi\epsilon_0R ##

IF I can replace all the spherical capacitors with parallel plate capacitors with the same capacitance, I can solve the problem very easily. Though this seems intuitive, it yields the incorrect result.
Looking forward on how to approach this problem.
 
on Phys.org
Three spheres.webp
Here is your approach. Look at the figure on the right. Each colored region of space encloses equipotential conductors in the steady state.

Start by finding expressions for the potential difference between each sphere and infinity. Then find expressions for the potential differences ##V_{AB}## and ##V_{BC}.##
 
Last edited:
kuruman said:
View attachment 365510Here is your approach. Look at the figure on the right. Each colored region of space encloses equipotential conductors in the steady state.

Start by finding expressions for the potential difference between each sphere and infinity. Then find expressions for the potential differences ##V_{AB}## and ##V_{BC}.##
let me try this
 
kuruman said:
View attachment 365510Here is your approach. Look at the figure on the right. Each colored region of space encloses equipotential conductors in the steady state.

Start by finding expressions for the potential difference between each sphere and infinity. Then find expressions for the potential differences ##V_{AB}## and ##V_{BC}.##
sorry, long time but I feel I've tried enough. not getting how to proceed. trying to use V=Q/C