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Electric Charges and Static Electricity

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                Electric Charges and Static Electricity
Electric Charges and Atoms                                       For example, if you rub a balloon on your hair, some
                                                                 electrons rub off your hair onto the balloon. The
Electricity is a form of energy that is made when
                                                                 balloon has gained electrons, so it now has a negative
electrons move. What makes electrons move? The
                                                                 charge. Your hair has lost electrons, so it has a
electric charges of different particles in atoms.
                                                                 positive charge.
Atoms are made up of protons, neutrons, and
electrons. Protons have a positive charge (+).                   The balloon has more negative     Her hair has more positive
                                                                 charges than positive charges.    charges than negative charges.
Electrons have a negative charge (-). Neutrons
have no charge.

                                          Electron
                                    -     (negative charge)



                        + +
             Proton
    (positive charge)


                            Neutron
                 -          (no charge)



Charges that are alike repel, or push against, each
                                                                 If you hold the balloon near your head, your positively
other. Unlike charges attract, or pull toward, each
                                                                 charged hair will be attracted to the negatively
other.
                                                                 charged balloon. You may hear a crackling sound and

  -                     -
                              Two electrons have like            see a tiny spark. The crackling sound and spark are
                              charges. They repel, or push
                              against, each other.               produced as the electrons jump
                                                                 from from the balloon to
                                                                 your hair.


 +                      +
                              Two protons have like charges.     If you rub two balloons
                              They repel, or push against,
                              each other.
                                                                 on your head or a piece
                                                                 of wool, both balloons
                                                                 will be negatively
                                                                 charged. If you try to
  +                     -
                              A proton and an electron have
                              unlike charges. They attract, or   touch the two balloons
                              pull toward, each other.           together, they will
                                                                 repel each other.

A negatively charged object will attract a positively
charged object and repel another negatively charged                                               Balloons that have been
one. Two positively charged objects will also repel                                               “charged” in this way may
each other.                                                                                       also pick up tiny bits of
                                                                                                  paper!
Static Electricity                                                                                Lightning is another
Have you ever gotten a shock or made a spark by                                                   product of static
shuffling your feet on the carpet? If so, you've                                                  electricity. Lightning is a
experienced static electricity.                                                                   huge electric spark that
Static electricity is produced by a buildup of                                                    jumps from a negatively
electric charges on an object. This happens when                                                  charged cloud to a
electrons move from one object to another. If                                                     positively charged object
electrons rub off one object and stick onto another,                                              on the ground.
that object becomes negatively charged.
                                                                                                                     GRADE

    SHOW WHAT YOU KNOW!                                       Electric Charges & Static Electricity
                                                                                                                       5
        DIRECTIONS: Answer these questions without looking at the information page. Check your answers
        using the key. If any of your answers are incorrect, go back and reread the information about this topic
        before you take the test again.


1   A balloon has a negative charge. A glass rod has                4    Two positively charged objects will __.
    a positive charge.
                                                                         A attract each other
                                                                         B   repel each other
                                                                         C not affect each other
               balloon                 glass                             D become a neutrally charged object
                                       rod


                                                                    5    Which of the following is not an effect of static
                                                                         electricity?
    What will happen when the glass rod is brought
    near the balloon?                                                    A A student shuffles his feet on a carpet, then
                                                                           gets a shock as he touches a doorknob.
    A The balloon will be attracted to the rod.
                                                                         B   Lightning strikes the ground during a storm.
    B   The balloon will be repelled by the rod.
                                                                         C A student rubs a balloon on her head, then
    C The balloon will remain in place.                                    finds that she can pick up tiny pieces of paper
                                                                           with the balloon.
    D The balloon will spin in circles.
                                                                         D A student rubs a balloon on her head, then
                                                                           finds that she can see electrons on the balloon.
2   A negatively charged object will __.
    A repel a positively charged object
                                                                    6    The pictures below show three atoms. Which
    B   repel a neutron                                                  choice correctly shows the charges of the
    C not affect a positively charged object                             particles.
    D attract a positively charged object                            A                   B                   C
                                                                                   -                   -                    +
                                                                              +                   +
                                                                             + +                                     - -
3   This image shows 2 balloons repelling.                                    +                   +
                                                                         -                   -                   +

                                                                         A
                                                                         B
                                                                         C
                                                                         D Both A and C are correct.


                                                                    7    If electrons rub off one object and stick onto
    What causes them to repel?                                           another, that object becomes __.

    A An equal number of protons.                                        A positively charged

    B   An unequal number of neutrons.                                   B   negatively charged

    C An unequal number of electrons.                                    C neutrally charged

    D An equal number of electrons.                                      D Both A and C are correct.
 Use the picture below to answer questions 8-11.         13   Static electricity is associated with __.
                                                              A the gain of negative charges (electrons)
                                      -   Z                   B   the gain or loss of neutral charges (neutrons)
                                                              C the loss of negative charges (electrons)
                   X   + +                                    D Both A and C are correct.


                            Y                            14   Static electricity is produced by a buildup of
                 -                                            electric charges on an object. This happens
                                                              when __.

8    Which particle is shown at X?                            A electrons move from one object to another

     A A proton.                                              B   protons move from one object to another

     B   A neutron.                                           C neutrons move from one object to another

     C An electron.                                           D Both A and B are correct.

     D A carbon.
                                                         15   Which diagram correctly shows what will
                                                              happen if two electrically charged particles are
9    Which particle is shown at Y?                            near each other?
     A A proton.
     B   A neutron.                                                    A        +                    +
     C An electron.
     D A carbon.                                                       B        +                    -
10   Which particle is shown at Z?
     A A proton.
                                                                       C      -                  -
     B   A neutron.                                           A A only.

     C An electron.                                           B   B only.

     D A carbon.                                              C A and C are correct.
                                                              D A, B, and C are correct.
11   What is the charge of the particle shown at Z?
     A Positive.                                         16   What is the electric charge of this teacher's
                                                              hair?
     B   Negative.
     C Neutral.
     D Repelled.


12   Which statement about electricity is correct?
     A Electricity is a form of energy that is made
       when electrons move.
     B   Electricity is a form of energy that is made
         when protons move.
     C Electricity is a form of heat that is made when        A positively charged
       protons move.                                          B   negatively charged
     D Electricity is a form of energy that is made           C neutrally charged
       when neutrons move.                                    D Both A and C are correct.

				
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