Demonstrating static electricity with Scotch Tape and a table
In this experiment, we will magically force electrons from Scotch Tape to pass to and from a table. Of course, you won’t be able to see the electrons transfer, but you will definitely see the effects of the hopping electrons. The device we will create can further be used to test the charge of any object you want.
- Fill the 2 film cans about 3/4 full of clay.
- Place 2 straws, side by side, in each of the film cans. Push the straws down into the clay.
- Bend the flexible ends of the straw so they are horizontal (parallel to the table you are working on).
- Position the straws, by twisting them, so that the horizontal arms of the straw face away from each other in opposite directions (it’ll look sort of like a TV antenna or the letter ‘T’). Make sure the arms are the same height.
- Tear off two 3–4-inch pieces of tape. Press them onto a flat table. Place them near the edge of the table so that a small piece of the tape is available to use as a ‘handle’.
- Grab the ‘handle’ of the tape and quickly rip it off of the table.
- Stick a piece of the tape onto the ‘arm’ of one of the straws so that the tape dangles downward off of the extended straw arm. Now place the other piece of tape in the same manner, onto one of the straws in the second film canister.
- At this point you should have 2 film cans, each with two straws sticking up, horizontal arms extended in opposite directions (sort of looks like the letter ‘T’). One of the straws in each container should have a small piece of tape stuck to the ‘T’ and hanging downward.
- Now, place the cans next to each other, about 6 inches apart. Move and turn the cans so that the pieces of tape become close together with their flat sides facing each other.
See how the tapes repel each other. Both pieces of tape are ‘charged’ with the same type of charge (either positive or negative, depending upon the surface of the table you used). Like charges will repel each other. This charge occurred due to the jumping of negative charges, or electrons, from the tape to the table. The tape actually lost electrons, and the table gained them.
- Now tear off 2 more pieces of tape. Press the sticky side of one piece of tape to the smooth side of the other. Leave a small piece of one of the tapes sticking out so that it is available as a ‘handle’.
- Now quickly rip the pieces of tape apart and stick them to the two remaining arms.
- Move and turn the cans to bring these 2 arms (with the pieces of tape we just stuck on them) close together.
Notice how these pieces of tape attract each other—the same principle as above. When you ripped the tapes apart, electrons jumped from one piece of tape to the other. One piece of tape is now positively charged, and the other is negatively charged. And remember, opposite charges attract each other.
- Run a comb through your hair a few times.
- Place it next to each of the pieces of tape. Notice which ones it repels and which ones it attracts.
See how the comb acts with each piece of tape. Remember the two pieces of tape that we stuck together? The one that was stuck on its sticky side should attract to the comb. The comb will repel the one that was stuck on the smooth side. In this case, the comb is negatively charged.
An unusual exception
Strangely enough, the other two pieces of tape (that we ripped off the tabletop) will react differently depending on the type of table you used in the experiment. Some plastic types of tables cause the tapes to repel (indicating that the tape has a negative charge), and other types of table surfaces will cause an attraction (indicating that the tape has a positive charge).
These charges result from the electrons jumping from one object to the other. They can pass from the table to the tape or from tape to tape. One object loses electrons, and the other gains them. This concept is the basis for many well-known phenomena, such as lightning, static electricity, and magnetism.
Now you can test the charges of various objects using these new devices. All you have to know is the charge of the piece of tape you are using and remember that opposite charges attract and like charges repel. You can use the comb to test the charges of each piece of tape since the comb will always be negatively charged. One little tip though – the charges will slowly leak away, so they must periodically be recharged by sticking them back together and ripping them apart again.
Supplies required for the static electricity experiment
Supplies: Tape, Comb, Straw, Film canister
Image Credits
In-Article Image Credits
Static electricity raises girl's hair on playground slide via Wikimedia Commons by Chris Darling with usage type - Public Domain. October 2, 2005Styrofoam peanuts clinging to a cat's fur due to static electricity via Wikimedia Commons by Sean McGrath with usage type - Creative Commons License. February 1, 2006
Featured Image Credit
Styrofoam peanuts clinging to a cat's fur due to static electricity via Wikimedia Commons by Sean McGrath with usage type - Creative Commons License. February 1, 2006