ELECTRONIC PRINCIPLES - OD1647 - LESSON 1/TASK 1
magnetic forces act is known as the magnetic field.
A pattern of this directional force can be obtained by
performing an experiment with iron filings (figure 3). A piece
of glass is placed over a bar magnet, and the iron filings are
then sprinkled on the surface of the glass. The magnetizing
force of the magnet will be felt through the glass, and each
iron filing becomes a temporary magnet. If the glass is now
tapped gently, the iron particles will align themselves with the
magnetic( field surrounding the magnet, just as the compass
needle did previously. The filings form a definite pattern,
which is a visible representation of the forces comprising the
magnetic field. Examination of the arrangements of iron filings
at the poles and weakens as the distance from the poles
increases. It is also apparent that the magnetic field extends
from one pole to the other, constituting a loop about the magnet.
FIGURE 3. PATTERN FORMED BY IRON FILINGS.