What’s Your Idea?
Physics –Magnetism
The students are discussing what makes a material magnetic.
A material has to be made of a specific
type of metal to attract a magnet.
Yes I agree. Any other metal will repel
a magnet.
I disagree. Anything that is made of
metal is magnetic.
Materials like wood and plastic are not
magnetic, but they don’t repel a magnet.
?
Possible Points of Discussion
A material has to be made of a specific type of metal to attract a magnet.
Only iron, cobalt and nickel are magnetic materials. They are all a type of
metal. Alloys (mixtures of two or more metals) can be magnetic if they
contain enough of a type of magnetic metal, e.g. steel, which contains a
high proportion of iron.
Yes I agree. Any other metal will
repel a magnet.
All other metals are non-magnetic,
and will not react to a magnet. This
means they will not be attracted by
or repelled by a magnet. If a
material is repelled, it is pushed
away. Non-magnetic materials are
not repelled – they just do nothing.
Possible Points of Discussion
I disagree. Anything that is made
of metal is magnetic.
Alloys (mixtures of two or more
metals) can be magnetic if they
contain enough of a type of
magnetic metal, e.g. steel, which
contains a high proportion of iron.
For a metal to be magnetic it must
contain some magnetic metal: iron,
nickel or cobalt.
Materials like wood and plastic
are not magnetic, but they don’t
repel a magnet.
Non-magnetic materials are not
repelled – they just do nothing.
The students are discussing how to make an electromagnet stronger.
Use more coils in the wire.
Use less coils in the wire.
Increase the current in the wire.
Reduce the current in the wire.
?
Possible Points of Discussion
Use less coils in the wire.
Use more coils in the wire.
When the wire of a circuit is
wrapped into a coil, the magnetic
field becomes stronger. Increasing
the number of coils in the wire
(solenoid) will increase the
strength of the electromagnet.
Reduce the current in the wire.
Increase the current in the wire.
The current flowing through the
wire generates a magnetic field
around it. Increasing the current
that flows through the wire
will increase the strength of
the electromagnet.
The students are comparing the Earth to a magnet.
It has a north pole and south pole
like a magnet.
It’s not shaped like a magnet.
Magnets are always bars.
It’s because the core of the Earth is
made of iron.
The Earth is not magnetic. If I drop
something metal on the Earth, I can
always pick it up.
?
Possible Points of Discussion
It has a north pole and south pole
like a magnet.
The Earth has a magnetic north
and south pole, which behave in a
similar way to that of the north
and south poles of a bar magnet by
producing a magnetic field.
It’s not shaped like a magnet.
Magnets are always bars.
Although the Earth is roughly
spherical in shape, the mantle of
the Earth’s structure moves and
creates a magnetic field. It is
because of this that the Earth
behaves like a magnet.
Possible Points of Discussion
It’s because the core of the Earth
is made of iron.
Iron is a magnetic metal, which
may have something to do with
the cause of the Earth’s magnetic
field, however scientists do not
have a definitive understanding of
how the magnetic field is produced.
The Earth is not magnetic. If
I drop something metal on the
Earth, I can always pick it up.
The Earth generates a magnetic
field. However, the Earth itself is
not largely made of magnetic
materials.