<h2>Compare how magnetic forces act through non-magnetic materials and
</h2><h2>magnetic materials:</h2>
Explanation:
Magnet
• Magnet :- is an object which attracts pieces of iron, steel etc towards itself.
Some facts about magnets:-
• When magnet is freely suspended it always align towards north-south direction
• Like poles always repel & opp. poles attract each other.
• Magnet always exist as dipole
• Two poles can never be separated : if we try to cut it then still both the poles will exist even ina small piece of magnet .it automatically develops the lost polarity
Magnet always develop certain area around it where its effect can be felt ie. magnetic field.
MAGNETIC Field
is studied by drawing imaginary lines called magnetic lines of forces.
Characteristics.
• They always originate from North pole & terminate at South pole. This shows that if north pole was free is move it would have mvre towards south pole.
•Place where they are closer indicate strong M. field i.e. at poles.
•Mag. Field lines gives the direction of magnetic force.
•Two magnetic lines will never intersect each other as they give direction of force & force can’t have 2 direction at a time.
- M Field lines are closed continuous curves.
This is what that happens in magnetic materials .
Non magnetic materials
- Magnetic forces 'act through' non-magnetic materials
- These magnetic materials can be used as a shield around a magnet.
- The domain theory of magnetism tries to explain why metals get magnetised
- . The magnetic elements have little molecular magnets inside them.
- Magnets attract only the magnetic materials
Types of magnetic materials
Soft magnetic materials (e.g. iron) have domains that easily move into line when the metal is placed in a magnetic field but as soon as the field is removed the domains take on a random pattern again. It returns to being unmagnetized straight away.
Hard magnetic materials (e.g. steel) have domains that do not easily move into line when the metal is placed in a magnetic field, a strong field is needed for some time, but then, when the field is removed the domains retain the magnetic pattern. The metal stays magnetic for a long time.
