How Much Work is Required to Move a Charge Between Equipotential Surfaces?

AI Thread Summary
The work required to move a charge between equipotential surfaces is zero, as no work is done when moving a charge between points of equal potential. The discussion emphasizes that the net change in potential energy is zero when returning to the original surface. Participants suggest visualizing the concept using the analogy of rolling a ball up and down a hill, where the work done by gravity cancels out. The initial query about calculating work using the equation U = U2 - U1 is clarified, reinforcing that the work done in this scenario is independent of the path taken. Understanding this principle is crucial for solving problems related to electric potential and work.
blackout85
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The work in joules required to carry a 6.0 C charge from a 5.0 V equipotential surface to a 6.0V equipotential surface and back again to the 5.0V surface is:

A) 0
B) 1.2 X 10^-5
C) 3.0 X 10^-5
D) 6.0 X 10^-5
E) 6.0X10^-6

Can someone please explain how to start off doing this problem. I thought that it involved the equation U= U2-U1= W. But, I am unsure how you connect the two.

Thank you
 
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You can think of this in terms of the net change in potential energy and the total work done, as you did.

Or you can think of it this way -- how much work did it take to move the charge one way? Then how much work did it take to move the charge back?

It helps your intuition if you think of the situation as rolling a ball up a hill. How much work does gravity do when you roll a ball up a hill? How much work does gravity do when the ball rolls back down?
 
The answer then would have to be zero. Am I right to think that
 
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