2 Problems involving electric field and work

AI Thread Summary
The discussion revolves around two problems involving electric fields and work done by charges. The first problem questions whether the work done by a charge moving from point z to y would differ if the path included an intermediate point x, with the conclusion that the work remains the same due to consistent potential differences. The second problem addresses calculating the electric field at point z, with initial assumptions about charge cancellation leading to confusion about direction. Clarification is sought regarding the behavior of electric fields when opposite charges are present, particularly when a test charge is placed in the field. The conversation emphasizes the importance of understanding electric field direction and the implications of charge interactions.
nutella
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Homework Statement


Excuse my excellent paint skills
http://imgur.com/PbXdlOW
If the work done by a charge from z to y is W. Would the work be different if it was from z to x then to y.

Homework Equations


W=vQ

The Attempt at a Solution


I said it would be the same because delta v would be the same in the end

1. The problem state, all variables and give/known data
http://imgur.com/RkG05ph
What is the electric field at the point z and what is the direction

Homework Equations


E=kq/r^2

The Attempt at a Solution


I assume the positive and negative would cancel each other out. The distance between the charge and the center is d rad(2)/2 so the charge for one of them would be KQ/(2d^2/4)= 2KQ/d^2 then you just multiply that by 2 because there is two charges, but i don't know the direction
 

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The fact that you don't know the direction in the last problem is an indication that you did something wrong. Can you justify
nutella said:
I assume the positive and negative would cancel each other out.
 
My teacher showed us a problem where the opposite corners were opposite charges and he said the electric field at the middle is zero.
 
What happens if you put a test charge in the middle?
 

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