In a common physics demonstration, a rubber rod is first rubbed vigorously on silk or fur. It is then brought close to a small Styrofoam™ ball, which it attracts. If you then touch the ball with the rod, it suddenly repels the ball. Why does it first attract the ball, and why does it then repel the same ball?

In a common physics demonstration, a rubber rod is first rubbed vigorously on silk or fur. It is then brought close to a small Styrofoam™ ball, which it attracts. If you then touch the ball with the rod, it suddenly repels the ball. Why does it first attract the ball, and why does it then repel the same ball?

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter19: Electric Forces And Electric Fields

Section: Chapter Questions

Problem 15CQ: A common demonstration involves charging a rubber balloon, which is an insulator, by rubbing it on...

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