# Point Charges

1. Homework Statement
q1 (-6.5E-7 C) @ 6 cm to the right of origin (X,Y coordinate is 6,0)
q2 (6.5E-7 C) @ 21 cm to the left of origin (X,Y coordinate is -21,0)

At the half-way point of these two charges, what is the E field value...?

2. Homework Equations
sum of electric fields
electric field at point is equal to constant times the charge, all divided by radius squared
constant is 8.99E9 Nmm/(CC)

3. The Attempt at a Solution
I found the two E's from the point to the half-way mark...I'm suppose to add the two E's because it's going from negative to positive...right? Well...I got it wrong...

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kdv
1. Homework Statement
q1 (-6.5E-7 C) @ 6 cm to the right of origin (X,Y coordinate is 6,0)
q2 (6.5E-7 C) @ 21 cm to the left of origin (X,Y coordinate is -21,0)

At the half-way point of these two charges, what is the E field value...?

2. Homework Equations
sum of electric fields
electric field at point is equal to constant times the charge, all divided by radius squared
constant is 8.99E9 Nmm/(CC)

3. The Attempt at a Solution
I found the two E's from the point to the half-way mark...I'm suppose to add the two E's because it's going from negative to positive...right? Well...I got it wrong...

What did you use for the distance when you calculated the E field?

What did you use for the distance when you calculated the E field?
Rather dumb question to ask...but I used .135 m as R.

hage567
Homework Helper
Rather dumb question to ask...but I used .135 m as R.
It is not a dumb question at all. You didn't show your work. How can we tell you what you did wrong if you don't show any calculations?

kdv
Rather dumb question to ask...but I used .135 m as R.
well, if it's a dumb question to ask I won't ask any question anymore.

Best luck