Do now! - MrSimonPorter

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Transcript Do now! - MrSimonPorter

Do now!
You have 2 minutes to play
with your magnets.
What do you need to know about
magnets?
ALL magnets have two poles
NORTH seeking pole
SOUTH seeking pole
Breaking a magnet produces two
magnets!
N
N
S
N
S
S
N
S
Opposites attract!
Opposite poles attract and like poles repel
Magnetic materials
Magnetic materials
Iron (steel), Cobalt
and Nickel
Magnetic induction
Magnetic induction
When a magnetic material is close to a
magnet, it becomes a magnet itself
magnet
S
N
S
We say it has induced magnetism
N
Hard and Soft Magnetism
Soft Magnetism
Pure iron is a soft magnetic material
before
S
N
S
after
N
S
NN
Not a
magnet
Iron nail
It is easy to magnetise but loses its
magnetism easily
Hard Magnetism
Steel is a hard magnetic material
before
S
after
N
S
S
N
NN
S
N
It’s a
magnet!
Steel paper
clip
It is harder to magnetise, but keeps its
magnetism (it is used to make magnets!)
Magnetic fields
I wonder if this is
a magnetic
field?
Magnetic fields
Magnets (and electric currents) produce
magnetic fields around them.
In the magnetic field, another magnet or
magnetic material will experience a magnetic
force.
Magnetic field lines
We can represent the magnetic field
around a magnet using field lines.
Magnetic field lines
The arrows show the direction a compass
needle would point at that point in the field.
Magnetic field lines
The arrows show the direction a compass
needle would point at that point in the field.
The closer the field lines
are, the stronger the
magnetic force felt
Field around a bar magnet
Earth’s Magnetic Field
Remember the
North of a compass
needle points to the
geographic north
pole (i.e. the
geographic North
pole is a magnetic
south pole!)
Draw the sentence
Draw the sentence
1. Magnets ALWAYS have two poles, North and South.
2. Opposite poles attract, and like poles repel.
3. Iron (steel), cobalt and nickel are the only elements that are
attracted to magnets.
4. When a magnetic material is close to a magnet, it becomes a
magnet itself.
5. Iron is a SOFT magnetic material;it is easily magnetised but
easily loses its magnetism.
6. Steel is a HARD magnetic material; it is hard to magnetise
but keeps its magnetism.
7. The magnetic field around a bar magnet is shaped like a
burger, with lines and arrows going from N to S.
8. Nottingham is the home of good football.