Neutral Hair,
Get Charged?
When you comb your hair, friction changes the number of electrons on it. The friction takes electrons off the hair and puts them on the comb, especially if your hair is dry. So both your hair and the comb become charged objects.
ell, that’s it for the theory. Now you’re ready to discover the simple rules that all charged objects must obey. For this investigation you’ll need:
Some thread
Dry hair
Piece of wool cloth
Before we begin, you should be aware that high humidity reduces static electricity. Best results will be obtained during the drier months.
Try rubbing the second comb briskly with a piece of wool cloth (sheep hair). As with
human hair, the comb removes electrons from the wool, which leaves the wool with a charge opposite that of the comb.
5.
Bring the wool cloth near the charged side of the hanging comb. Do you
get the same
result as before?
What happens?
So you’ve got another
important rule:
OPPOSITE CHARGES?
3.
Bring it near the charged side of the hanging comb, but don’t
let the two combs touch. Remember what you see.
Since both combs had the same charge, you now know how two objects with the same charges will act:
SAME CHARGES?
Remember this rule. Any two objects with the same charge will react the same way.
1.
Tie a piece of thread to the center of one comb. Charge the
comb by running it through your hair briskly several times. Hang the comb
as pictured, being careful not to touch the part of the comb that went
through your hair (the charged part).
2.
Charge up a second combin the same way.