Holding Charge

None needed.

Note: This Snack works best when done on a dry, low-humidity day.

Tear off one end of the wrapper on a new straw. 

With one hand, tightly hold the newly exposed plastic straw. With the other hand, gently yet firmly grasp the remaining paper wrapper.

Quickly slide the wrapper back and forth over the straw. Keep sliding it until the straw and wrapper feels warm (10 strokes should do the trick).

Remove the wrapper and immediately place the straw on a smooth, clean vertical surface where it will stick.

Try doing this experiment again. See what else you can stick your straw to.

Did you get a charge out of this? You sure did. You electrically charged the straw by causing negatively and positively charged particles to move around.

After rubbing it with its paper wrapper, the straw has more negatively charged particles left on it. This makes the straw negatively charged. When you bring your negatively charged straw near a neutral object, like your palm, it pushes away electrons in your palm and induces a local positive charge. Since opposites attract, the straw sticks to your hand.

Here are some other things to try:

• Hold two charged straws vertically next to each other. What do you feel?
• Lift small objects with your charged straw: salt, pepper, and confetti, for example.
• Use your straw to roll an empty soda can.
• Rub other materials on your straw to see what happens.

Rubbing two dissimilar materials together can generate static electricity. Use this activity as an introduction to the phenomenon known as the triboelectric effect. This can lead to investigating other materials that will create static electricity.