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AsadaShino92
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Homework Statement
A conducting sphere of radius 100cm is charged to a potential of 30 volts.
a) What is the charge on the sphere?
b) What is the energy stored in the field?
c) If the sphere is connected to a second identical uncharged sphere by a long wire, what is the final energy in the system? You can neglect any interference.
Homework Equations
Q=CV
C=4πεr
U=(1/2)CV^2
The Attempt at a Solution
For part A I find the capacitance of the sphere so I can then apply Q=CV to find the charge.
C=4π(8.85X10^-12)(100)=1.1X10^-8
Q=(1.1X10^-8)(30)=3.3X10^-7
For part B I used the energy equation U=(1/2)(1.1X10^-8)(900)=4.95X10^-6
I am pretty much stuck on part C. Since it is a conducting sphere the potential for both of them should be the same. So I tried equating both potential equations such as V=(kq1)/(r)=(kq2)/(r). Both spheres are identical so I get that q1=q2. Not really clear on how to find the final energy.