Question

which change will decrease the electric force between two positively charged objects?
moving them closer together
moving them farther apart
adding neutrons
removing electrons

Explanation:

To solve this, we use Coulomb's Law for electric force between two charges, \( F = k\frac{q_1q_2}{r^2} \), where \( F \) is force, \( k \) is a constant, \( q_1, q_2 \) are charges, and \( r \) is the distance between them.

• Moving closer (\( r \) decreases) increases \( F \) (since \( F \) is inversely proportional to \( r^2 \)), so this is incorrect.
• Moving farther apart (\( r \) increases) decreases \( F \) (as \( r \) in the denominator increases, \( F \) decreases), which matches the requirement.
• Adding neutrons: Neutrons have no charge, so this doesn't affect the electric force (which depends on charge), so incorrect.
• Removing electrons from positively charged objects would make them more positive (increase \( q_1, q_2 \)), increasing \( F \) (since \( F \) is proportional to \( q_1q_2 \)), so incorrect.

Answer:

B. moving them farther apart (assuming the options are labeled as A: moving them closer together, B: moving them farther apart, C: adding neutrons, D: removing electrons)