Objective:

To demonstrate static electricity and to use it to explain how positive and negative charges are attracted to each other. This knowledge of static electricity should also be related to phenomena in the atmosphere such as lightning.

Standards:

Properties of Earth Materials (physical and chemical properties of water), Structure of the Earth System (atmospheric composition and properties at different elevations; clouds – formation and impact on weather and climate), Structure of Atoms (properties of matter, atoms, and smaller components), and Structure and Properties of Matter (atoms interact with one another; the physical properties of compounds reflect molecule interaction).

Materials:

tap water and a comb.

Procedure:

Turn on the water faucet to allow a thin stream of water to flow.

Comb your air approximately thirty times or for approximately thirty seconds.

Hold the comb near the stream of water without touching the water.

Observe what happens.

Science behind It:

By combing your hair, you charged your hair with static electric charges. This caused the comb to become primarily negatively charged. Water on the other hand is positively charged, and since opposite charges attract, the negative charges from the comb attracted the positive charges of the water. This attraction is what caused the stream of water to bend towards the comb. Static electricity, like that demonstrated here, is the driving mechanism behind lightning in the atmosphere. When storm clouds form, negative charges build up in the bottom of the clouds and strive to reach the positive charges of Earth’s surface. When the difference between these charges becomes great enough, lightning strikes as the negative charges “jump” from the clouds to the ground.