Magnets and Magnetic Fields

what is meant by a uniform magnetic field?

a field that exerts a constant force over a region

opposite poles _________

attract

if the magnet and magnetic material are brought _______ the induced magnetism will be ________

closer stronger

hard magnetic materials can be magnetised _______, and once magnetised can ______ ______ _________ __________

easily retain their magnetism permanently

is steel a hard or soft magnetic material?

hard

this magnetism has been ________ by the original magnet

induced

two examples of magnetic substances 'i____ and s_____'

iron and steel

Step 2) Investigating the shape and direction of the magnetic field of a bar magnet using plotting compasses

label the magnet's poles

magnetic field lines

lines that indicate the size, shape and direction of a magnetic field

soft magnetic materials are easily

magnetised and demagnetised

Step 4) Investigating the shape and direction of the magnetic field of a bar magnet using plotting compasses

mark the position of the head of the compass with a dot

Step 5) Investigating the shape and direction of the magnetic field of a bar magnet using plotting compasses

move the compass so the end of the compass needle matches up with the dot

magnetic field line arrows always point from ' _______ to ______'

north to south

soft magnetic materials - they will ___ _______ any _______ magnetism

not retain permanent

what does a uniform magnetic field consist of?

parallel, equally spaced magnetic field lines

Step 3) Investigating the shape and direction of the magnetic field of a bar magnet using plotting compasses

place a plotting compass near one pole of the magnet

Step 1) Investigating the shape and direction of the magnetic field of a bar magnet using plotting compasses

place the bar magnet in the middle of a piece of paper and trace the magnet's outline

magnetic fields

regions where magnetic materials experience a force

like poles _______

repel

Step 3) Investigating the shape of the magnetic field of a bar magnet using iron filings

scatter the paper with small iron filings

is iron a hard or soft magnetic material?

soft

Result - Investigating the shape of the magnetic field of a bar magnet using iron filings

the filings line up in the shape of the magnetic field

Advantage of using plotting compasses to investigate a magnetic field

they show the shape and direction of the magnetic field

Step 2) Investigating the shape of the magnetic field of a bar magnet using iron filings

trace round the bar magnet and then place the magnet under the piece of paper

placing the north and south poles of two permanent bar magnets near each other creates a ________ ______ _______ between the two magnets

uniform magnetic field

why can magnets also attract other magnetic substances?

(because) when a magnetic is brought near a magnetic material and when therefore the magnetic material is in a magnetic field, the material acts as a magnet

Step 6) Investigating the shape and direction of the magnetic field of a bar magnet using PLOTTING COMPASSES

Continue the process at different points along the magnet

Step 1) Investigating the shape of the magnetic field of a bar magnet using iron filings

Place permanent bar magnet on top of a piece of paper