Calculating Potential from electric field problem

AI Thread Summary
The discussion revolves around calculating the work done by an electric field from a nonconducting sheet with a given surface charge density and the resulting electric potential at a specified distance. The confusion arises regarding the sign of the work done when moving a charge from the sheet to a point away from it, with the solution manual indicating a positive value. Clarification is sought on the direction of the electric force and the movement of the charge, which determines the sign of the work done. Additionally, there is uncertainty about the formula for electric potential and how to derive it from the electric field. Understanding these concepts is crucial for accurately solving the problem.
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Homework Statement



An infinite, nonconducting sheet has a surface charge density σ = +8.77 pC/m2. (a) How much work is done by the electric field due to the sheet if a particle of charge q0 = 9.61 x 10-19 C is moved from the sheet to a point P at distance d = 2.45 cm from the sheet? (b) If the electric potential V is defined to be zero on the sheet, what is V at P?

Shouldnt the answer for part a be negative, because the solution manual says its positive,. I know V=-W_{}infty/q . Can someone explain me why this is so ?
 
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(a) First answer 2 questions:
1. What's the direction of the force due to the electric sheet (i.e., away from or towards the sheet)?
2. In what direction does the charge move (towards or away from the sheet)?
The work done is positive if those two things are in the same direction, or negative if they're in opposite directions.

(b)
I don't understand your formula for V the way it is written.
How would you calculate V, given the electric field E?
 

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