Rubber rods charged by rubbing with cat fur repel each other. Glass rods charged by rubbing with silk repel each other. A rubber rod and a glass rod charged respectively as above attract each other. A possible explanation is that all rubber rods always have an excess of positive charge on them.

Question

Quizplus · Accepted Answer

Rubber rods charged by rubbing with cat fur typically acquire a negative charge, while glass rods charged by rubbing with silk acquire a positive charge. The attraction between a rubber rod and a glass rod is due to the opposite charges (positive on glass, negative on rubber), not because rubber rods always have an excess of positive charge.

Rubber Rods Charged by Rubbing with Cat Fur Repel Each