In Scenario 2, with one positive red ball and one negative blue ball on a smooth surface, when a second positive red ball is placed between them, the blue ball tends to move toward the middle red ball while the other red ball moves away. Which forces explain this behavior?

In Scenario 2, with one positive red ball and one negative blue ball on a smooth surface, when a second positive red ball is placed between them, the blue ball tends to move toward the middle red ball while the other red ball moves away. Which forces explain this behavior?

• A. Gravitational forces
• B. Magnetic forces
• C. Electrical attraction and repulsion
• D. Friction

Answer: (C)

Electric forces between charges explain what you see. The red balls are positive and the blue ball is negative, so opposite charges attract and like charges repel. When a second positive ball is placed between the blue ball and the other red ball, the blue ball is pulled toward the nearby positive ball (attraction to the middle red). At the same time, the two positive red balls push away from each other (repulsion between like charges), so the outer red ball moves away. On a smooth surface with little friction, these electric forces cause the blue ball to move toward the middle red ball while the other red ball shifts away. Gravity and friction don’t create this horizontal attraction/repulsion pattern, and magnetic forces aren’t in play here since there’s no magnet or moving charges involved.

Electric forces between charges explain what you see. The red balls are positive and the blue ball is negative, so opposite charges attract and like charges repel. When a second positive ball is placed between the blue ball and the other red ball, the blue ball is pulled toward the nearby positive ball (attraction to the middle red). At the same time, the two positive red balls push away from each other (repulsion between like charges), so the outer red ball moves away. On a smooth surface with little friction, these electric forces cause the blue ball to move toward the middle red ball while the other red ball shifts away. Gravity and friction don’t create this horizontal attraction/repulsion pattern, and magnetic forces aren’t in play here since there’s no magnet or moving charges involved.