Advertisements
Advertisements
Question
How do you account for the following fact?
Soft iron keepers help to prevent the magnets from losing their magnetic properties.
Advertisements
Solution
In magnets, external fields like earth’s magnetic field can randomize the domains. Perhaps stray fields caused by flowing currents in nearby electric circuits can also disturb i the alignment of domains lying inside a magnet. Given enough time, such magnets may find their domains randomly oriented and hence their net magnetisation may get lost. A keeper for magnets is just a strong permanent magnet that keeps all the domains pointing the same way and realign those that may have gone astray and hence magnet, can retain its magnetism for a long time.
APPEARS IN
RELATED QUESTIONS
Copy the figure below which shows a plotting compass and a magnet. Label the N pole of the magnet and draw field line on which the compass lines
What is a lodestone?
What do you understand by the term magnetic field lines?
Explain why iron filings which are sprinkled on a sheet of cardboard placed over a bar magnet take up a definite pattern when cardboard is slightly tapped.
Figure. shows a bar magnet placed on the table top with its north pole pointing towards south. The arrow shows the north-south direction. There are no other magnets or magnetic materials nearby.

Insert two magnetic field lines on either side of the magnet using arrow head to show the direction of each field line.
Write a note on the 'magnetic field'.
State any two properties of a magnet.
The magnetic field lines always begin from ____________.
Name the poles P, Q, Rand S of the magnets in the following figures 'a' and 'b':
![]() |
![]() |
| Figure 'a' | Figure 'b' |


