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Can water be bent? By a comb? That is not placed inside the water stream? Judge for yourself with this clever experiment that illustrates the power and effect of invisible static electricity, the kid of electricity that is all around us and that we and objects create all the time through simple interaction.

• A nylon comb
• A water faucet

1. Adjust the faucet so that a small amount of water pours forth. The stream should be about 1.5 millimeters (or 1/16th of an inch) in diameter.
2. Run the comb through your hair a couple of times
3. Slowly bring the teeth of the comb near (but not immersed in) the stream of water, about 8-10 cm (3 or 4 inches) below the faucet.
4. When the teeth of the comb are about an inch or less away from the stream, the stream should bend toward the comb.
5. Try moving the comb closer to the stream. How does the distance between the stream and the comb affect how much the stream bends?
6. Comb your hair again and try it again. Does it bend the water more? How about if you turn the faucet on a little more? What about a bit less water streaming out? Test out other combs to see if there are differences. How about other people’s hair?

Why It Works:

Static electricity is the accumulation of electrical charge in an object. The charge is created when two objects are rubbed against each other. When this happens, some electrons jump from one object to the other. The object that loses the electrons becomes positively charged, whereas the recipient becomes negatively charged.

The charge on the comb attracts the molecules of the water in the stream. Because the molecules in the stream are easily influenced, the stream bends towards the comb.