A point charge Q is placed at the mid-point of a line joining two charges, 4 q and q. if the net force on charges q is 0, then Q must be equal to
Correct answer: D. +4q
- A. -q
- B. +q
- C. -2q
- D. +4q
Explanation
Let's denote the two charges as +4q and q and the distance between them as 2d. The point charge Q is placed at the midpoint, which means it is equidistant from both +4q and q.We can find the answer using the formula:F= k q1.q2/r2
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Electrostatics describes forces between charges through Coulomb's law, electric fields and field intensity, then uses electric potential to measure energy per unit charge. Capacitors store charge and electrical energy, with capacitance depending on geometry and dielectric material, not simply on the amount of charge present.
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