If two point charges have the same sign, the electrostatic force between them is

If two point charges have the same sign, the electrostatic force between them is

• A. Repulsive
• B. Attractive
• C. Zero
• D. Infinite

Answer: (A)

Two point charges interact via Coulomb’s law, F = k q1 q2 / r^2. The sign of the product q1 q2 determines the nature of the force. When the charges have the same sign, their product is positive, which means the force is repulsive: each charge experiences a push away from the other along the line connecting them. The magnitude decreases with distance as 1/r^2, but the direction is always away from the other charge for like charges. This is why the correct description is repulsive. The force is not zero (unless a charge is zero or they’re infinitely far apart) and not infinite.

Two point charges interact via Coulomb’s law, F = k q1 q2 / r^2. The sign of the product q1 q2 determines the nature of the force. When the charges have the same sign, their product is positive, which means the force is repulsive: each charge experiences a push away from the other along the line connecting them. The magnitude decreases with distance as 1/r^2, but the direction is always away from the other charge for like charges. This is why the correct description is repulsive. The force is not zero (unless a charge is zero or they’re infinitely far apart) and not infinite.