Plotting Magnetic Fields
Plotting Magnetic Field Lines
Plotting Magnetic Field Lines
In your examination you might be asked to describe a method of plotting the magnetic field around a bar magnet
There are two principle ways of doing this:
Using Iron Filings
Place a piece of paper on top of the magnet
Gently sprinkle iron filings on top of the paper
Now carefully tap the paper to allow the iron filings to settle on the field lines
Magnetic Field Shown Using Iron Filings
Iron filings can be used to plot a magnetic field
Place the magnet on top of a piece of paper
Draw a dot at one end of the magnet (near its corner)
Place a plotting compass next to the dot, so that one end of the needle of the compass points towards the dot
Use a pencil to draw a new dot at the other side of the compass needle
Now move the compass so that it points towards the new dot, and repeat the above process
Keep repeating until you have a chain of dots going from one end of the magnet to the other. Then remove the compass, and link the dots using a smooth curve – the magnetic field line
The direction of the field line is the same as the direction of the plotting compass
You can now repeat the whole process several times to create several other magnetic field lines
Magnetic Field Shown Using Plotting Compasses
Compasses can be used to plot the magnetic field around a bar magnet