Charges q,q,and -q are placed on the x-axis at x = 0,x = 6 m,and x = 12 m,respectively.At which of the following points does the electric field have the greatest magnitude?

Question

Charges q,q,and -q are placed on the x-axis at x = 0,x = 6 m,and x = 12 m,respectively.At which of the following points does the electric field have the greatest magnitude?
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Quizplus · Accepted Answer

The electric field is strongest when the distance from a charge is smallest, and weakest when the distance is greatest. Therefore, at x = 5 m and x = 14 m, the electric field is the weakest because there is a greater distance between the point and the charges. At x = 11 m, the electric field due to the two positive charges cancels out the electric field due to the negative charge, so the net electric field is zero. At x = 9 m, however, the point is closer to the positive charge at x = 6 m than to the negative charge at x = 12 m, so the electric field due to the positive charge is stronger than the electric field due to the negative charge. Therefore, the electric field at x = 9 m is the strongest.

Charges Q,q,and -Q Are Placed on the X-Axis at X