A point charge of 10 µ C is placed at the origin. At what location on the X -axis should a point charge of 40 µ C be placed so that the net electric field is zero at x = 2 cm on the X -axis ?

Step-by-step solution

Let the charge 40   μC be placed at a distance X 0 from the origin as shown in the figure. For the electric field at x = 2 to be 0 , E P = 0 ⇒ k × 10 2 2 = k × 40   X 0 - 2 2 ⇒ 1 2 = 2 X 0 - 2 ⇒ X 0 - 2 = 4 Therefore, the charge is located at X 0 = 4 + 2 = 6   cm