Electric Field of Two Unequal Point Charges

AI Thread Summary
For two point charges of the same positive charge, the electric field at the midpoint is zero. When one charge is double the other, the electric field will not be zero at the midpoint. To find the point where the electric field equals zero, one must use the equation E = kQ/r, where k is a constant, Q is the charge, and r is the distance from the charge. The discussion emphasizes the need to show calculations to determine the specific point between the charges where the electric field cancels out. Understanding the relationship between charge magnitudes and distances is crucial for solving this problem.
dystorsion
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For two point charges of the same charge (positive) that are placed a distance from each other "r", the electric field in the midpoint of r is zero.

Now here's my question, what if one point charge had double the charge of the other? At what point between the two charges the electric field equal zero?

Thanks,
Dystorsion
 
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dystorsion said:
For two point charges of the same charge (positive) that are placed a distance from each other "r", the electric field in the midpoint of r is zero.

Now here's my question, what if one point charge had double the charge of the other? At what point between the two charges the electric field equal zero?

Thanks,
Dystorsion

You have to show some work before people will answer this question.

What is the equation for an electric field of a point charge?
 
My bad, I assumed that people would know.

E = kQ/r

where k is the constant of 9.0E9, Q is the charge of the point charge, and r is the distance from the point charge.
 
dystorsion said:
My bad, I assumed that people would know.

E = kQ/r

where k is the constant of 9.0E9, Q is the charge of the point charge, and r is the distance from the point charge.

I forgot the units, can you give me those too?

What is the electric field of two point charges at a distance r?
 
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