MAKING OBJECTS ATTRACT OR REPEL
Tie an 8-inch length of string around a plastic spoon, and label the spoon #1.
Suspend it from a ruler or stick secured on a table so that it hangs on its side.
Label a second plastic spoon #2, and bring it close to the bowl of the first spoon
until the two spoons almost touch.
Now rub both sides of the bowl of spoon #1 several times with a piece of sandwich
wrap, then rebalance the spoon. Rub #2 the same way, then bring the bowls of both
spoons close together. (They should move apart.)
Why is this?
The particles that make up atoms have electrical charges. Scientists say that each
proton has a positive charge, and each electron has a negative charge.
When plastic spoons are rubbed with sandwich wrap, electrons from the atoms in
the spoons are transferred to the wrap, leaving the spoons with more protons
(positive charges) and giving the wrap more electrons (negative charges).
Therefore, when the two positively charged spoons are brought together, they repel
Now number two balloons, and hang balloon #1 from a ruler with a string. Rub the
balloon with a piece of wool. (Try not to make too much wind near the balloon,
because wind blowing around the balloon can make it difficult to observe what
Rub balloon #2 in the same way, and bring the balloons together. (They will repel
each other.) When balloons are rubbed with wool, electrons are brushed from the
atoms in the wool and are transferred to the balloons, leaving the wool with a
positive charge and giving the balloons a negative charge. Next, rub spoon #1 with
sandwich wrap, and make sure it is balanced. Then rub balloon #2 with wool, and
slowly bring it close to the spoon. (The objects will attract each other.) From these
tests, you will realize that when their electrical charges are alike, objects repel each
other; when their electrical charges are different, objects attract each other. In the
atom, the electron is attracted to the proton because their charges are not alike. Is
this what people mean when they say that "opposites attract?"
Any problems with this page? Send URL to
webmaster. Thank you!
We publish two newsletters a couple of times a month. To
subscribe, send a blank email to the appropriate email address. Topica
will send you a message asking if you really intended to subscribe - just click
reply - that's it!
Free Recipe Collection Newsletter:
Jewish Recipe Collection Newsletter:
Tired of Geek Speak when
you have Computer Questions?