Electric field and potential of 2 point charges

AI Thread Summary
To determine where the electric field is zero between a -2 μC charge and a 10 μC charge separated by 15 cm, one must analyze the direction of the electric fields produced by each charge. The electric field from the positive charge points away from it, while the field from the negative charge points towards it, indicating that the point where the fields cancel must be outside the two charges. For the electric potential to be zero, the contributions from both charges must balance, which can occur at a different location than where the electric field is zero. Visualizing the scenario with a diagram helps clarify the positions where these conditions are met. Understanding the behavior of electric fields and potentials is crucial for solving such problems effectively.
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Homework Statement



A -2 μC charge and a 10μC charge are separated by 15.0cm. At what point is the electric field zero? At what point is the electric potential zero?


Homework Equations


E=(kq1/r1^2)+(kq2/r2^2)
V=kq1/r1 + kq2/r2

The Attempt at a Solution


My main problem is with finding the direction in which the negative and positive charges act on the point where the electric field is 0 and where the electric potential is 0. Can someone explain how to figure out the direction that these charges act? For the electric field, how do you know whether the point is between the two charges, or on either side of one of the charges? I think I can figure out the math from there.
 
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Obviously, The Electric Fields due to the two charges should point in opposite direction for the net E to be zero at that point. You should draw a diagram and see where is/are the possible places.
 
Okay, makes more sense now. Thanks!
 
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