Final answer:
You would alter q3 such that its force on q2 counteracts the force from q1, causing the net force on q2 to be zero. This is based on Coulomb's law, which states that the force between two charges is proportional to their magnitudes and inversely proportional to the square of the distance between them.
Step-by-step explanation:
In terms of physics, specifically electric forces, you would change q3 such that its force on q2 exactly counteracts the force from q1 on q2. Coulomb's Law, which describes the force between two charges, will be used for this calculation. According to the law, the force between two charges is directly proportional to the product of their magnitudes and inversely proportional to the square of the distance between them. So, in this situation, you'd want the electric force exerted by q1 and q3 on q2 to be equal but in opposite directions, hence cancelling each other out and making the net force on q2 equal to zero.
For instance, consider the charges q1 and q2 are positive. If we keep the q3 at the same distance from q2 as q1 but on the opposite side, then to balance the forces, q3 should be negative if q1 is positive, to ensure the forces due to q1 and q3 on q2 are equal and opposite, thereby cancelling out.
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