Physics - Magnetism: Flashcards
(45 cards)
Names of magnetic materials.
Iron (Fe)
Cobalt (Co)
Nickel (Ni)
Some metals are made out of magnetic materials making them magnetic, but they aren’t really magnetic materials, an example of this is steel.
Non-magnetic materials examples
Aluminium
Copper
Silver
NOT ALL METALS ARE MAGNETIC
ONLY MAGNETIC MATERIALS CAN BECOME MAGNETS
Difference of magnet and magnetic material
1 end attracts. £Bothends have to attract because the magnet would…
A magnetic material can become a magnet
All materials that are magnetic attract to a magnet.
WHAT MAGNETIC MATERIALS ARE MAGNETS AND WHAT MATERIALS ARE JUST MAGNETIC MATERIALS:
MAGNET: MAGNETIC MATERIAL:
…induce/transfer… #1 end *repels*. …opposite poles onto magnetic material, if North Pole touches… …magnetic material then magnetic material turns south and vice… …versa - not permanent magnet. £**No**ends can **repel** £**No** ends can have the force of **repulsion** £**All** ends *have to* have the force of **attraction**
See law of magnetism for more info.
Types of pole
- NORTH-SEEKING POLE/NORTH POLE (N)
- SOUTH-SEEKING POLE/SOUTH POLE (S)
All magnets have 2 poles, one of each type (see above). Can not EVER have magnet with ONE pole.
Magnetism is strongest at…
…the poles
THE LAWS OF MAGNETISM
Magnets can exert forces on other magnets
Like poles (n and n also s and s) repel
Opposite poles attract
Magnets can exert forces on unmagnetised magnetic materials
Both poles always attract unmagnetised magnetic materials.
THE LAWS OF MAGNETISM 2: …Both poles attract to unmagnetised magnetic materials because…
Temporary poles have to be transferred onto iron nails/unmagnetised metal materials.
See Physics - 2ND FORM - MAGNETISM REVISION in photos if got yellow or under.
LAWS OF MAGNETISM 2:
For both poles to always attract temporary poles must be transferred onto iron nail/unmagnetised
object
Magnetism is strongest at its poles
LAWS OF MAGNETISM EXPERIMENT:
1.take 2 watch glasses and arrange a bar magnet on the top.
2. Take another magnet and bring the 2 north poles together notate what happens (do not bring them close together so that they ‘stick’ together/repel away).
3.bring south and south together and notate what happens (do not bring them close together so that they attract together/repel away)
4. Bring the North Pole to the South Pole notate what happens (do not bring them close together so that they ‘stick’ together/ repel apart)
5. substitute bar magnet for unmagnetised iron nail and bring the North Pole, then the south after, to the unmagnetised iron nail notate what happens (do not bring them close together so that they attach together/ repel apart)
SEE PHOTO OF WATCH GLASSES TOGETHER IN MAGNETISM PHYSICS REVISION - 2ND FORM IN PHOTOS.
Recall a brief summary of LAWS OF MAGNETISM PROVING EXPERIMENT
- Put bar magnet on 2 watch glasses
Add second magnet and…
…2. Record results of:
@ put north and north together
@ put south and south together
@ put north and south together - Replace magnet with unmagnetised iron nail and
@ put north towards 1 end of nail
@ put **south*& towards 1 end of the nail
4.Record results - SEE DIAGRAM IN MAGNETISM PHYSICS revision - 2ND FORM IN PHOTOS HAVE TO DO.
To induce a Pole…
…one must use a permanent magnet (that they know is a magnet for sure) and bring it towards a magnetic material.
Experiment to test for whether a magnetic material is a magnet or non-magnetic material
- Take a bar magnet (permanent) and bring close to material if both the north and south ends attract to the bar magnet then the material is a magnetic material.
- Non-magnetic materials don’t attract or repel when near a permanent magnet.
- Take a permanent magnet and bring close to material
If 1 end repels and 1 attracts to permanent magnet then material is a magnet
Bar magnets and horseshoe magnets are…
…permanent magnets
Experiment for magnetism
IF object/material + bar magnet = attracts, it is a magnet.
ON THE OTHER HAND, IF object/material + bar magnet = NOT REPEL (the object/material can only attract or repel it is a magnet) nothing happens, then it is nota magnz et or magnetised material
/strength of the forces…
…vary from the distance form the poles
Experiment: strength of magnet
- Weigh iron block with no extra force actions on it use weight as control variable
2.clamp a bar magnet above the iron block (5mm) note the mass.
3, repeat but make the distance 10mm, 15mm etc (5 up each time) and measure mass each time.
MAGNETIC FIELD
The space around a magnet where forces are felt.
Can be plotted and drawn as a diagram
Diagram of magnetic field gives information about the size and direction of the magnetic force.
Plot and draw magnetic fields
Use iron filings:
1, pour iron filings onto paper with bar magnet underneath
2, gently tap edge of paper until lines start appearing.
3, The lines of magnetic field may not be fully formed - need large paper.
Using compass:
1, stick the bar magnet down on paper.
2, choose a point touching the magnet and draw a dot
3, use compass, align the north needle with the dot and draw another dot where the end of the needle (south) is pointing
4, repeat all round the magnet.
See Photos in MAGNETISM PHYSICS REVISION -2ND FORM
Magnet field lines go from…
…North to south SEE MAGNETISM PHYSICS -2ND FORM IN PHOTOS PLEASE.
SEE MAGNETISM PHYSICS -2ND FORM IN PHOTOS AND CONCENTRATE..
..know how to interpret field diagrams
Compass - how it works
Arrow inside of it = a small and vey lightmagnet with poles
Low weight helps it to rotate freely.
Arrow points in the directions of the MAGNETIC FORCE MAGNETIC FORCE
North + south = attract
North-seeking pole of compass doesn’t point directly to South Pole.
SEE PHOTOS - MAGNETISM PHYSICS-2ND FROM
Earth has…
It’s own magnetic field.
The motion of liquid iron outer core generates Earth’s magnetic field
On a compass/ really light magnet with no friction/ forces acting against it, the North Pole is actually the north-seekingpole meaning it seeks north and because earths poles are flipped it means the north-seeking pole is pointing to earths South Pole
See photos magnetism physicsi 2nd form
A compass points…
…to Earth’s south geographical poel