What is the Work Required to Charge a Spherical Shell?

AI Thread Summary
To calculate the work required to charge a spherical shell of radius R and total charge Q, one must consider the relationship between work and electric potential energy. The work done is equivalent to the change in potential energy as the shell is charged. The relevant formula involves integrating the electric field around the shell, which is influenced by its spherical symmetry. The final answer for the work done is k * Q^2 / (2R), where k is the Coulomb's constant. Understanding the implications of the shell's geometry is crucial for solving the problem effectively.
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the problem is: "Calculate the work that must be done to charge a spherical shell of radius R and total charge Q", and I have no idea where to start. You probably have to write some sort of an integral but I don't know how. Can anyone give me a hint?
 
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the answer, by the way is ke*Q^2/(2R), if that helps
 
Think about the equivalence of work and energy, and the fact that charging a sphere changes the electric potential energy.
 
I know that work is equal to the change of potential energy, but the potential energy of what? Won't it be just keQ/r^2. How does the fact that it is a spherical shell affect the problem?
 
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