Solving Electric Field Equations: A Case Study

AI Thread Summary
The discussion focuses on solving electric field equations using the formula E=ke*q/r². The participant is struggling with the correct formulation of the electric field components and recognizes that the equations for force and electric field should differ. They provide their initial equations for the i and j components but receive feedback indicating an error in their use of square roots. The suggestion is to correct the square root in their equations and to apply the relationship F = q*E to derive the force from the electric field. Clarifying these points will help resolve the confusion in their calculations.
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Homework Statement


Screenshot2011-01-28at123342PM.png



Homework Equations


E=ke*q/r2


The Attempt at a Solution


See screenshot. The angles are correct, however I can't get the equation right for either part. I understand they should be different since one is force and the other electric field, I thought that should be the electric field solved and simplified.

Not sure how to put in equations on here, so I'll do my best.
before simplification, I had for the i component:
ke3q/a2+sqrt(2)/2*ke4q/a2

and for the j component:
ke5q/a2+sqrt(2)/2*ke4q/a2


where have I gone wrong? the sqrt(2)/2 is cos(45) and sin(45) to get the components of the Bq in the drawing. Not sure what the problem is. I can do these fine with numbers so maybe I just am not putting it into the computer right. suggestions?
 
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Ei = ke3q/a²+sqrt(2)/2*ke4q/a² = kq/a²[3 + 2√2]
In the screenshot, you have √2 when you should have 2√2.
Same in the j part.

Use F = q*E to get the force - same expression, just square the q.
 
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