Download Please Do Now! - Bloomsburg Area School District

What is the biggest
magnet in the world?
Read pg. 578 in the
science book your
teacher gave you to
find out. Write your
answer in the margin
at the top of the page.
A magnet is an object or a
material that can attract metals
containing iron, nickel, or cobalt.
Magnets can attract and repel
each other.
All magnets have a north pole
and a south pole
The north poles and south poles
of two magnets will repel each
other.
The attraction of magnets is
strongest when magnets are
close together.
A magnetic field is the area of
magnetic force around a magnet.
Read the section on pg. 579
in the science book your teacher
gave you entitled Using a
Compass to build your own
compass with your partner.
In the margin of your
paper explain how a
compass works.
An electromagnet is a coil of wire
wrapped around a metal core;
current moving through the wire
can be turned off with a switch.
Electromagnets are often used to
power electric motors.
Almost all electricity is produced
by generators.
Generators produce back-andforth current called alternating
current. Batteries produce
current in one direction, called
direct current.
Air, steam,
and water
turn
turbines.
Electricity from a power plant is
carried to a series of
transformers.
Each transformer in the series
increases or decreases the
current’s voltage until it is at the
right level to enter your home.
Do you think there is a difference
between the simple motor used in
the electric cars you parents may
drive and the model cars you and
your friends may race?
All electric motors have a power
source, a magnet, a rotating loop
of wire, and a motor shaft. The
only difference is the type or size
of the power source. If model
cars are remote controlled, then
electromagnets can also be used
to power the electric motors.