Everything is made up of tiny things called atoms.
An atom contains three different kinds of even smaller particles.
These tiny particles are too small to be seen. They are called
protons, neutrons, and electrons. Look at the picture of the atom
Notice the neutrons and protons are found in the center,
and the electrons move rapidly around it. Protons and
electrons have a property we call charge. Protons have a
positive charge and electrons have a negative charge. Protons and
electrons have opposite charges of equal size. The plus units are
called "positive" and the minus units
"negative." Neutrons have no charge. They are
It is a basic law of nature that similar charges repel
each other. Repel means push each other away. Opposite charges
attract each other.
Usually, atoms have an equal number of protons and
electrons. There are cases when this changes. Take for example
when you comb your hair. As you comb your hair some of the electrons
are transferred from your hair to the surface of the comb. Now the
comb has more negative (electrons) than positive (protons) charges.
If you take the comb and place it near small bits of paper you notice the
bits of paper are attracted to the comb. The attraction between the
positive charge of the paper and the negative charge on the surface of the
comb is so strong they stick together. This is called
static electricity. Another example of static electricity is socks
sticking together when they come out of the dryer.
Directions: Answer the questions below about
1. Everything is made up of tiny things called
2. Protons have a
(+) units are positive.
4. Neutrons have no charge. They are
5. Electrons have a
(-) units are negative.
7. Where are the protons and neutrons found in an atom?
8. Which of the following means to "push away?"
9. Which of the following statements is true?
charges repel each other.
Similar charges attract each
10. Which of the following statements is true?
charges attract each other.
charges repel each other.
11. Static electricity occurs when
things are wet
12. Static electricity occurs because
number of protons and electrons are the same
the number of protons and
electrons are different
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