Which statement about electric forces is always true?

Which statement about electric forces is always true?

• A. Neutral objects are always repelled by charged objects.
• B. Charges do not exert force over distance.
• C. Like charges repel and opposite charges attract.
• D. Electric forces are weaker than gravity.

Answer: (C)

Like charges repel and opposite charges attract, and this directional rule is what electric forces follow in electrostatics. Coulomb’s law says the force between two point charges points along the line between them and depends on the product of the charges divided by the square of the distance between them. If the charges share the same sign, the force is repulsive; if they have opposite signs, the force is attractive. That sign-dependent behavior is why that statement is always true. Neutral objects aren’t necessarily repelled by a charged object. A charged object can polarize a neutral object, creating an induced attraction that pulls the neutral object in. Also, while the force weakens with distance, it does not disappear entirely at finite separations, so charges do exert force over distance. And electric forces are not inherently weaker than gravity; in most cases the electric interaction between charges is much stronger than gravitational attraction, so the idea that electric forces are always weaker isn’t universal.

Like charges repel and opposite charges attract, and this directional rule is what electric forces follow in electrostatics. Coulomb’s law says the force between two point charges points along the line between them and depends on the product of the charges divided by the square of the distance between them. If the charges share the same sign, the force is repulsive; if they have opposite signs, the force is attractive. That sign-dependent behavior is why that statement is always true.

Neutral objects aren’t necessarily repelled by a charged object. A charged object can polarize a neutral object, creating an induced attraction that pulls the neutral object in. Also, while the force weakens with distance, it does not disappear entirely at finite separations, so charges do exert force over distance. And electric forces are not inherently weaker than gravity; in most cases the electric interaction between charges is much stronger than gravitational attraction, so the idea that electric forces are always weaker isn’t universal.