Transcript The Electricity and Magnetism Connection

The Electricity and
Magnetism Connection
Chapter 5 Activity 3
What happens when you put the magnet
near the compass? How does this
happen?
The compass points to the magnet.
 If the magnet is next to the compass the
needle goes crazy.
 The needle is a magnetized metal so it is
attracted to the magnet itself
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Warm-Up
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Read “What Do You
Think” on page 264.
Record you ideas
about this question in
your comp book
Now discuss your
answers with the
person sitting next to
you
Activity

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Read and Answer the “For You To Do” on
pages265-267
Make sure to record you answer in you comp
book
For You To Do
Review – Electricity and Magnetism
Connection
What does it mean?
How do we know?
We can make magnet using
electricity and we can use
electricity to make a magnet.
This is what is meant by the
electricity and magnetism
connection.
We put the wire with the
battery and the wire became
magnetic. Because when you
run a electricity through a
wire it makes a magnetic
field.
Why do we believe?
Why should I care?
Metal detectors use electricity to power
magnets that can detect metals. If the find
a strong metal the metal detector goes off
letting us know that someone has a lot of
metal.
Why do we believe?
Magnetic Fields
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An Electric current has a
magnetic field. For a long,
straight wire, the magnetic
field makes concentric
circles around the wire.
As distance from the wire
increases, the field
becomes weaker. To make
a stronger field, bend the
wire into a loop.
Magnetic Fields continued
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A changing magnetic field
through a loop of wire induces
a current in the wire.
Moving the loop near a
magnet produces such a
changing field (because the
magnetic field is not uniform).
Through this process, which is
called current induction,
generators in power plants
produce electricity. Current
induction depends only on
relative motion
Magnetism continued
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In Step 12, you will
connect several batteries
in series to increase the
current through the
electromagnet.
Increasing the current will
increase the strength of
the electromagnet, But
there is a limit to this
increase, because once all
the domains are lined up,
no further magnetism can
be obtained from the nail.
This effect is called
saturation.