Calculating Electric Field at Origin due to Two Point Charges

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To calculate the net electric field at the origin due to two point charges, q1 (-4 nC) and q2 (+6 nC), the distances from the origin must be considered correctly. The electric fields generated by each charge should be treated as vectors, requiring decomposition into x and y components before summation. The initial approach incorrectly added the magnitudes without accounting for direction. Understanding this vector addition is crucial for obtaining the correct result. Properly applying these principles will lead to an accurate calculation of the electric field at the origin.
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A point charge q1 -4 nC is at the point x = 0.600 m, y = 0.800 m, and a second point charge q2 +6 nC is at the point x = 0.600 m, y = 0.
I need to calculate the magnitude of the net electric field at the origin due to these two point charges.
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|....... q1 (0.6, 0.8)
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|
|
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Origin--------------------q2 (0.6, 0)
To solve this problem I was thinking of taking the distances of q1 and q2 from the origin and using that as the radius, I can plug into
E = 1/(4piEo) * q1/r^2 r = 1 q1= -4nC
and
E = 1/(4piEo) * q2/r^2 r = 0.6 q2= +6nC
and add them together to find the electric field at the origin.
however when I did that, the answer turned out to be incorrect.
What am I'm doing wrong? Thakn you for your help.
 
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Your distances are correct, but you're ignoring the fact that the electric fields from the two charges need to be added as vectors, not just numbers. You need to split the fields into components in the x and y directions, then add them.

Does that help?
 
ohh i understand now! thankyou@!
 
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