Calculating the Increase in Energy for a Capacitor with Concentric Spheres

AI Thread Summary
The discussion centers on calculating the increase in energy for a capacitor made of two concentric spheres when the outer sphere is removed and then restored. Participants express confusion about the appropriate equations and methods to use, particularly regarding Gauss's law and the energy stored in charge configurations. The key points include the need to determine the electrostatic energy difference between the initial and final states of the capacitor. Additionally, there is a focus on understanding where the extra energy comes from when the spheres are separated. The conversation highlights the complexity of the topic and the need for clearer explanations and guidance.
renegade05
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Homework Statement


A capacitor consisting of two concentric spheres is arranged so that
the outer sphere can be separated and removed without disturbing the
charges on either. The radius of the inner sphere is a and that of the outer
sphere is b, and the charges are Q and -Q, respectively

a) If the outer sphere is removed and restored to its original form, find the
increase in energy when the two spheres are separated by a large distance.

b) Where does this extra energy come from?

Homework Equations



no idea

The Attempt at a Solution


no idea

The professor is teaching at a way higher level than necessary and I have no clue on what to do. Do I use gauss' law? maybe? I have no idea. please help
 
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How do you normally work out the energy stored in a configuration of charges?
You should have some notes on this.
 
@renegade05, think of difference of electrostatic energies between two cases. Capacity of spherical capacitor is:
phpYQUYwR.png

Capacity of isolated sphere is?
And formula for electrostatic energy you will use is?
 
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