Maximum Coulomb Force Condition – Rankers Physics

Coulomb's Law: Practice Problem & Solution

Two positive charges \(q_1\) and \(q_2\) having their sum \(Q\) are placed at \(d\) distance apart. For what values of the charges, the coulomb force between them will be maximum?
\(q_1 = \frac{Q}{4}, q_2 = \frac{3Q}{4}\)
\(q_1 = \frac{Q}{3}, q_2 = \frac{2Q}{3}\)
\(q_1 = \frac{Q}{2}, q_2 = \frac{Q}{2}\)
\(q_1 = \frac{Q}{5}, q_2 = \frac{4Q}{5}\)

Solution Explained:

To solve this problem, we apply the core principles of Coulomb's Law. Understanding the underlying formula is key to arriving at the correct answer below:

Coulomb force is proportional to the product \(q_1 q_2\). Since the sum \(q_1 + q_2 = Q\) is constant, the product is maximum when the charges are equal, i.e., \(q_1 = q_2 = Q/2\).

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