magnetism - magnetic fields Flashcards
what are the 4 types of magnetic material? what can they be made into?
iron, steel (alloy of iron), cobalt and nickel. all 4 of these materials can be made into a permanent magnet or an induced magnet
what is a magnetic field?
a region around a magnet where a force acts on another magnet or on a magnetic material
what happens when we place a magnetic material into a magnetic field?
it will experience a force of attraction towards the magnet
what happens to magnetic material when placed into magnetic field of a permanent magnet?
the magnetic material now becomes an induced magnet which is now attracted (force of attraction) to permanent magnet. the strength of magnetic fields depends on the distance from the magnet. closer = bigger attraction further away = smaller attraction
where is the field strongest?
at the poles of the magnet
what can direction of magnetic field be found with? how does it work?
a compass. a magnetic compass contains a small bar magnet. if we place compass near bar magnet we can plot magnetic field
how to plot magnetic field?
- place compass near the north pole of the bar magnet
- draw a cross at north pole of the compass
- move compass so south pole of compass is on the cross
- draw another cross at north pole of compass
- continue doing until you’ve plotted a complete magnetic field line
- connect all dots with a line and show direction of field line using an arrow (always north to south)
- repeat starting at different points from north pole of bar magnet
on a magnetic field drawing, what shows where field is strongest?
where the lines are closer together
where does needle point if we hold compass away from any magnets? what does this tell us?
North-South direction. this tell us earth has its own magnetic field. earth’s magnetic field is due to the earth’s core
