Exemplar Problemsr

Problem 3 : Three charges Q1, Q2, and Q3 are placed along the x-axis at positions (a, 0), (2a, 0), and (3a, 0), respectively. Find the point on the x-axis where the net electrostatic force on a positive charge placed there would be zero.

Solution :

Let’s place a positive test charge at a point (x, 0) on the x-axis. The net electrostatic force on this test charge due to Q1, Q2, and Q3 can be calculated using Coulomb’s law. Write expressions for the forces due to each charge, and then apply the superposition principle to find the net force. Set the net force equal to zero and solve for ‘x’ to find the point where the force is zero.