A negative point charge q1 = 25 nC is located on the y axis at y = 0 and a positive point charge q2 = 10 nC is located at y =14 cm. Find the y coordinate of the points where the net electric potential due to these two charges is zero.

 y = 0.1 m

Explanation:

The electrical power for point loads is

         V = k Sum qi / ri

in this case

         V = k ()

indicate that V = 0

        r₂ =

the distance r1 is

         r₁ = y -0

the distance r2

         r₂ = 0.14 -y

we substitute

        0.14 - y =  y

          y ( ) = 0.14

          y 1.4 = 0.14

          y = 0.14 / 1.4

          y = 0.1 m

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