What is an Ebonite Rod in Physics Experiments?

Ebonite is an extremely hard, black, and non-flexible material.

• It is actually highly vulcanized rubber (rubber mixed with a massive amount of sulfur and baked).
• It is named 'Ebonite' because it looks exactly like Ebony wood (a very dark, hard wood).
• Because it is rubber, it is an excellent electrical insulator.

To demonstrate the existence of electric charges, scientists use the friction method:

• The Action: Take an uncharged, neutral ebonite rod and rub it vigorously against a piece of dry animal fur, flannel, or wool.
• The Result: The friction causes tiny, negatively charged electrons to break off from the fur and stick onto the ebonite rod.
• The Charge: Because the ebonite rod gained extra electrons, it acquires a Negative Charge. (The fur, having lost electrons, is left with a Positive Charge).
• Now, if you bring this negatively charged ebonite rod near tiny pieces of dry paper, it will magically attract them.

In textbooks, the Ebonite rod is always compared to a Glass rod.

• If you rub a Glass Rod with Silk, electrons leave the glass and go to the silk. The glass rod becomes Positively Charged.
• If you bring the negatively charged Ebonite rod near the positively charged Glass rod, they will attract each other, proving the fundamental law: Opposite charges attract.