Although gravity can be an incredible force yet, it requires huge masses to observe its effects readily. It is not so with electricity. In fact, a minor charge can easily be observed using a tool that is often associated with uncovering the length of an object.
Things Required:
Wooden ruler
Balloon
Directions:
Position the wooden ruler so that it may balance on the edge of a table. At this balance point, the ruler remains steady with one end slightly lifted from the tabletop.
Charge up the balloon by stroking it through your hair or with a piece of wool. Slowly, approach the raised end of the ruler with the charged balloon. What happens? How does the electrostatic force work against the force of gravity?
This Is What Happens:
When the ruler was balanced, it remained still. As the charged balloon was brought over one end of the ruler, it upset the balance of charges of wood. The negatively charged balloon induced a positive charge in the near end of the ruler. This positive charge and the negative balloon attracted each other. The force of attraction was large enough to offset the balance of mass and cause the end of the ruler to rise up:
