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104 SCIENCE
10
Fun with Magnets
P
aheli and Boojho went to a place
where a lot of waste material was
piled into huge heaps. Something
exciting was happening! A crane was
moving towards the heap of junk. The
long hand of the crane lowered a block
over a heap. It then began to move.
Guess, what? Many pieces of iron junk
were sticking to the block, as it moved
away (Fig. 10.1)!
sticking to the holder. In some pencil
boxes, the lid fits tightly when we close
it even without a locking arrangement.
Such stickers, pin holders and pencil
boxes have magnets fitted inside
(Fig. 10.2). If you have any one of these
items, try to locate the magnets hidden
in these.
Fig. 10.1 Picking up pieces of iron from waste
Fig. 10.2 Some common items that have
magnets inside them
They had just read a very interesting
book on magnets and knew immediately
that there must be a magnet attached
to the end of the crane that was picking
up iron from the junk yard.
You might have seen magnets and
have even enjoyed playing with them.
Have you seen stickers that remain
attached  to iron surfaces like almirahs
or the doors of refrigerators? In some
pin holders, the pins seem to be
How Magnets Were Discovered
It is said that, there was a shepherd
named Magnes, who lived in ancient
Greece.  He used to take his herd of
sheep and goats to the nearby
mountains for grazing.  He would take
a stick with him to control his herd. The
stick had a small piece of iron attached
at one end.  One day he was surprised
to find that he had to pull hard to
free his stick from a rock on the
Rationalised 2023-24
Page 2


104 SCIENCE
10
Fun with Magnets
P
aheli and Boojho went to a place
where a lot of waste material was
piled into huge heaps. Something
exciting was happening! A crane was
moving towards the heap of junk. The
long hand of the crane lowered a block
over a heap. It then began to move.
Guess, what? Many pieces of iron junk
were sticking to the block, as it moved
away (Fig. 10.1)!
sticking to the holder. In some pencil
boxes, the lid fits tightly when we close
it even without a locking arrangement.
Such stickers, pin holders and pencil
boxes have magnets fitted inside
(Fig. 10.2). If you have any one of these
items, try to locate the magnets hidden
in these.
Fig. 10.1 Picking up pieces of iron from waste
Fig. 10.2 Some common items that have
magnets inside them
They had just read a very interesting
book on magnets and knew immediately
that there must be a magnet attached
to the end of the crane that was picking
up iron from the junk yard.
You might have seen magnets and
have even enjoyed playing with them.
Have you seen stickers that remain
attached  to iron surfaces like almirahs
or the doors of refrigerators? In some
pin holders, the pins seem to be
How Magnets Were Discovered
It is said that, there was a shepherd
named Magnes, who lived in ancient
Greece.  He used to take his herd of
sheep and goats to the nearby
mountains for grazing.  He would take
a stick with him to control his herd. The
stick had a small piece of iron attached
at one end.  One day he was surprised
to find that he had to pull hard to
free his stick from a rock on the
Rationalised 2023-24
105 FUN WITH MAGNETS
mountainside (Fig. 10.3). It seemed as
if the stick was being attracted by the
rock. The rock was a natural magnet
and it attracted the iron tip of the
shepherd's stick. It is said that this is
how natural magnets were discovered.
Such rocks were given the name
magnetite, perhaps after the name of that
shepherd. Magnetite contains iron.
Some people believe that magnetite was
first discovered at a place called
Magnesia. The substances having the
property of attracting iron are now known
as magnets.  This is how the story goes.
In any case, people now have
discovered that certain rocks have the
property of attracting pieces of iron. They
also found that small pieces of these
rocks have some special properties.
They named these naturally occurring
materials magnets. Later on the process
of making magnets from pieces of iron
was discovered. These are known as
artificial magnets. Nowadays artificial
magnets are prepared in different
shapes. For example, bar magnet, horse-
shoe magnet, cylindrical or a ball-ended
magnet. Fig.10.4 shows a few such
magnets.
Activity 1
Take a plastic or a paper cup. Fix it on a
stand with the help of a clamp as shown
in Fig. 10.5. Place a magnet inside the
cup and cover it with a paper so that
the magnet is not visible. Attach a
thread to a clip made of iron. Fix the
other end of the thread at the base of
the stand. (Mind you, the trick involved
here, is to keep the length of the thread
sufficiently short.) Bring the clip near
the base of the cup. The clip is raised in
air without support, like a kite.
Fig. 10.4 Magnets of different shapes
Fig.10.3  A natural magnet on a hillside!
Fig. 10.5  Effect of magnet - a paper clip
hanging in air!
Rationalised 2023-24
Page 3


104 SCIENCE
10
Fun with Magnets
P
aheli and Boojho went to a place
where a lot of waste material was
piled into huge heaps. Something
exciting was happening! A crane was
moving towards the heap of junk. The
long hand of the crane lowered a block
over a heap. It then began to move.
Guess, what? Many pieces of iron junk
were sticking to the block, as it moved
away (Fig. 10.1)!
sticking to the holder. In some pencil
boxes, the lid fits tightly when we close
it even without a locking arrangement.
Such stickers, pin holders and pencil
boxes have magnets fitted inside
(Fig. 10.2). If you have any one of these
items, try to locate the magnets hidden
in these.
Fig. 10.1 Picking up pieces of iron from waste
Fig. 10.2 Some common items that have
magnets inside them
They had just read a very interesting
book on magnets and knew immediately
that there must be a magnet attached
to the end of the crane that was picking
up iron from the junk yard.
You might have seen magnets and
have even enjoyed playing with them.
Have you seen stickers that remain
attached  to iron surfaces like almirahs
or the doors of refrigerators? In some
pin holders, the pins seem to be
How Magnets Were Discovered
It is said that, there was a shepherd
named Magnes, who lived in ancient
Greece.  He used to take his herd of
sheep and goats to the nearby
mountains for grazing.  He would take
a stick with him to control his herd. The
stick had a small piece of iron attached
at one end.  One day he was surprised
to find that he had to pull hard to
free his stick from a rock on the
Rationalised 2023-24
105 FUN WITH MAGNETS
mountainside (Fig. 10.3). It seemed as
if the stick was being attracted by the
rock. The rock was a natural magnet
and it attracted the iron tip of the
shepherd's stick. It is said that this is
how natural magnets were discovered.
Such rocks were given the name
magnetite, perhaps after the name of that
shepherd. Magnetite contains iron.
Some people believe that magnetite was
first discovered at a place called
Magnesia. The substances having the
property of attracting iron are now known
as magnets.  This is how the story goes.
In any case, people now have
discovered that certain rocks have the
property of attracting pieces of iron. They
also found that small pieces of these
rocks have some special properties.
They named these naturally occurring
materials magnets. Later on the process
of making magnets from pieces of iron
was discovered. These are known as
artificial magnets. Nowadays artificial
magnets are prepared in different
shapes. For example, bar magnet, horse-
shoe magnet, cylindrical or a ball-ended
magnet. Fig.10.4 shows a few such
magnets.
Activity 1
Take a plastic or a paper cup. Fix it on a
stand with the help of a clamp as shown
in Fig. 10.5. Place a magnet inside the
cup and cover it with a paper so that
the magnet is not visible. Attach a
thread to a clip made of iron. Fix the
other end of the thread at the base of
the stand. (Mind you, the trick involved
here, is to keep the length of the thread
sufficiently short.) Bring the clip near
the base of the cup. The clip is raised in
air without support, like a kite.
Fig. 10.4 Magnets of different shapes
Fig.10.3  A natural magnet on a hillside!
Fig. 10.5  Effect of magnet - a paper clip
hanging in air!
Rationalised 2023-24
106 SCIENCE
10.1 MAGNETIC AND NON-MAGNETIC
MATERIALS
Activity 2
Let us walk in the footsteps of Magnes.
Only, this time, we will change the
positions of the magnet and the iron.
There will be a magnet at the end of our
shepherd's stick. We can attach a small
magnet to a hockey stick, walking stick
or a cricket wicket with a tape or some
glue. Let us now go out on a "Magnes
walk" through the school playground.
What does our "Magnes stick" pick up
from the school ground? What about
objects in the classroom?
Collect various objects of day-to-day
use from your surroundings.  Test these
with the "Magnes stick". You can also
take a magnet, touch these objects with
it and observe which objects stick to the
magnet. Prepare a table in your
notebook as shown in Table 10.1. and
record your observations.
Look at the last column of Table 10.1
and note the objects that are attracted
by a magnet. Now, make a list of
materials from which these objects are
made. Is there any material common in
all the objects that were attracted by
the magnet?
We understand that magnet
attracts certain materials whereas some
do not get attracted towards magnet.
The materials which get attracted
towards a magnet are magnetic – for
example, iron, nickel or cobalt.  The
materials which are not attracted
towards a magnet are non-magnetic.
What materials did you find to be non-
magnetic from Table 10.1? Is soil a
magnetic or a non-magnetic material?
Table 10.1 Finding the objects attracted by magnet
Boojho has this question for you.
A tailor was stitching buttons on
his shirt.  The needle has slipped
from his hand on to the floor.
Can you help the tailor to
find the needle?
f o e m a N
t c e j b o e h t
f o e d a m s i t c e j b o e h t h c i h w l a i r e t a M
/ d o o w / m u i n i m u l a / c i t s a l p / h t o l C (
r e h t o y n a / n o r i / s s a l g
s e n g a M y b d e t c a r t t A
t e n g a m / k c i t s
) o N / s e Y (
l l a b n o r I n o r I s e Y
e l a c S c i t s a l P o N
e o h S r e h t a e L ?
Rationalised 2023-24
Page 4


104 SCIENCE
10
Fun with Magnets
P
aheli and Boojho went to a place
where a lot of waste material was
piled into huge heaps. Something
exciting was happening! A crane was
moving towards the heap of junk. The
long hand of the crane lowered a block
over a heap. It then began to move.
Guess, what? Many pieces of iron junk
were sticking to the block, as it moved
away (Fig. 10.1)!
sticking to the holder. In some pencil
boxes, the lid fits tightly when we close
it even without a locking arrangement.
Such stickers, pin holders and pencil
boxes have magnets fitted inside
(Fig. 10.2). If you have any one of these
items, try to locate the magnets hidden
in these.
Fig. 10.1 Picking up pieces of iron from waste
Fig. 10.2 Some common items that have
magnets inside them
They had just read a very interesting
book on magnets and knew immediately
that there must be a magnet attached
to the end of the crane that was picking
up iron from the junk yard.
You might have seen magnets and
have even enjoyed playing with them.
Have you seen stickers that remain
attached  to iron surfaces like almirahs
or the doors of refrigerators? In some
pin holders, the pins seem to be
How Magnets Were Discovered
It is said that, there was a shepherd
named Magnes, who lived in ancient
Greece.  He used to take his herd of
sheep and goats to the nearby
mountains for grazing.  He would take
a stick with him to control his herd. The
stick had a small piece of iron attached
at one end.  One day he was surprised
to find that he had to pull hard to
free his stick from a rock on the
Rationalised 2023-24
105 FUN WITH MAGNETS
mountainside (Fig. 10.3). It seemed as
if the stick was being attracted by the
rock. The rock was a natural magnet
and it attracted the iron tip of the
shepherd's stick. It is said that this is
how natural magnets were discovered.
Such rocks were given the name
magnetite, perhaps after the name of that
shepherd. Magnetite contains iron.
Some people believe that magnetite was
first discovered at a place called
Magnesia. The substances having the
property of attracting iron are now known
as magnets.  This is how the story goes.
In any case, people now have
discovered that certain rocks have the
property of attracting pieces of iron. They
also found that small pieces of these
rocks have some special properties.
They named these naturally occurring
materials magnets. Later on the process
of making magnets from pieces of iron
was discovered. These are known as
artificial magnets. Nowadays artificial
magnets are prepared in different
shapes. For example, bar magnet, horse-
shoe magnet, cylindrical or a ball-ended
magnet. Fig.10.4 shows a few such
magnets.
Activity 1
Take a plastic or a paper cup. Fix it on a
stand with the help of a clamp as shown
in Fig. 10.5. Place a magnet inside the
cup and cover it with a paper so that
the magnet is not visible. Attach a
thread to a clip made of iron. Fix the
other end of the thread at the base of
the stand. (Mind you, the trick involved
here, is to keep the length of the thread
sufficiently short.) Bring the clip near
the base of the cup. The clip is raised in
air without support, like a kite.
Fig. 10.4 Magnets of different shapes
Fig.10.3  A natural magnet on a hillside!
Fig. 10.5  Effect of magnet - a paper clip
hanging in air!
Rationalised 2023-24
106 SCIENCE
10.1 MAGNETIC AND NON-MAGNETIC
MATERIALS
Activity 2
Let us walk in the footsteps of Magnes.
Only, this time, we will change the
positions of the magnet and the iron.
There will be a magnet at the end of our
shepherd's stick. We can attach a small
magnet to a hockey stick, walking stick
or a cricket wicket with a tape or some
glue. Let us now go out on a "Magnes
walk" through the school playground.
What does our "Magnes stick" pick up
from the school ground? What about
objects in the classroom?
Collect various objects of day-to-day
use from your surroundings.  Test these
with the "Magnes stick". You can also
take a magnet, touch these objects with
it and observe which objects stick to the
magnet. Prepare a table in your
notebook as shown in Table 10.1. and
record your observations.
Look at the last column of Table 10.1
and note the objects that are attracted
by a magnet. Now, make a list of
materials from which these objects are
made. Is there any material common in
all the objects that were attracted by
the magnet?
We understand that magnet
attracts certain materials whereas some
do not get attracted towards magnet.
The materials which get attracted
towards a magnet are magnetic – for
example, iron, nickel or cobalt.  The
materials which are not attracted
towards a magnet are non-magnetic.
What materials did you find to be non-
magnetic from Table 10.1? Is soil a
magnetic or a non-magnetic material?
Table 10.1 Finding the objects attracted by magnet
Boojho has this question for you.
A tailor was stitching buttons on
his shirt.  The needle has slipped
from his hand on to the floor.
Can you help the tailor to
find the needle?
f o e m a N
t c e j b o e h t
f o e d a m s i t c e j b o e h t h c i h w l a i r e t a M
/ d o o w / m u i n i m u l a / c i t s a l p / h t o l C (
r e h t o y n a / n o r i / s s a l g
s e n g a M y b d e t c a r t t A
t e n g a m / k c i t s
) o N / s e Y (
l l a b n o r I n o r I s e Y
e l a c S c i t s a l P o N
e o h S r e h t a e L ?
Rationalised 2023-24
107 FUN WITH MAGNETS
If you fill this table and send it to
Paheli and Boojho, they can compare
the amount of iron filings found in soil
from different parts of the country. They
can share this information with you.
10.2 POLES OF MAGNET
We observed that iron filings (if they are
present) stick to a magnet rubbed in the
soil. Did you observe anything special
about the way they stick to the magnet?
Activity 4
Spread some iron filings on a sheet of
paper.  Now, place a bar magnet on this
sheet. What do you observe?  Do the iron
filings stick all over the magnet?  Do you
observe that more iron filings get attracted
to some parts of the magnet than others
(Fig. 10.7)? Remove the iron filings
sticking to the magnet and repeat the
Activity 3
Rub a magnet in the sand or soil.   Pull
out the magnet. Are there some particles
of sand or soil sticking to the magnet?
Now, gently shake the magnet to remove
the particles of sand or soil. Are some
particles still sticking to it? These might
be small pieces of iron (iron filings)
picked up from the soil.
Through such an activity, we can
find out whether the soil or sand from a
given place contains particles that have
iron. Try this activity near your home,
school or the places you visit on your
holidays. Does the magnet with iron
filings sticking to it, look like any one
of those shown in Fig. 10.6?
 Make  a table of what you find.
Fig. 10.6 Magnet with (a) many iron filings
(b) few iron filings and
(c) no iron filings sticking to it.
(a)
(b)
(c)
Table 10.2 Magnet rubbed in sand.
How many iron filings?
n o i t a c o l f o e m a N
d n a y n o l o C (
/ y t i c / n w o t
) e g a l l i v
n o r i d n i f u o y d i D
o t g n i k c i t s s g n i l i f
? t e n g a m e h t
/ w e f y r e v / y n a M (
) e n o n
activity. Do you observe any change in
the pattern with which the iron filings
get attracted by different parts of the
magnet? You can do this activity using
pins or iron nails in place of iron filings
and also with magnets of different shapes.
Draw a diagram to show the way iron
filings stick to the magnet. Is your drawing
similar to that shown in Fig. 10.6 (a)?
We find that the iron filings are
attracted more towards the region close
Fig. 10.7 Iron filings sticking to a bar magnet
Rationalised 2023-24
Page 5


104 SCIENCE
10
Fun with Magnets
P
aheli and Boojho went to a place
where a lot of waste material was
piled into huge heaps. Something
exciting was happening! A crane was
moving towards the heap of junk. The
long hand of the crane lowered a block
over a heap. It then began to move.
Guess, what? Many pieces of iron junk
were sticking to the block, as it moved
away (Fig. 10.1)!
sticking to the holder. In some pencil
boxes, the lid fits tightly when we close
it even without a locking arrangement.
Such stickers, pin holders and pencil
boxes have magnets fitted inside
(Fig. 10.2). If you have any one of these
items, try to locate the magnets hidden
in these.
Fig. 10.1 Picking up pieces of iron from waste
Fig. 10.2 Some common items that have
magnets inside them
They had just read a very interesting
book on magnets and knew immediately
that there must be a magnet attached
to the end of the crane that was picking
up iron from the junk yard.
You might have seen magnets and
have even enjoyed playing with them.
Have you seen stickers that remain
attached  to iron surfaces like almirahs
or the doors of refrigerators? In some
pin holders, the pins seem to be
How Magnets Were Discovered
It is said that, there was a shepherd
named Magnes, who lived in ancient
Greece.  He used to take his herd of
sheep and goats to the nearby
mountains for grazing.  He would take
a stick with him to control his herd. The
stick had a small piece of iron attached
at one end.  One day he was surprised
to find that he had to pull hard to
free his stick from a rock on the
Rationalised 2023-24
105 FUN WITH MAGNETS
mountainside (Fig. 10.3). It seemed as
if the stick was being attracted by the
rock. The rock was a natural magnet
and it attracted the iron tip of the
shepherd's stick. It is said that this is
how natural magnets were discovered.
Such rocks were given the name
magnetite, perhaps after the name of that
shepherd. Magnetite contains iron.
Some people believe that magnetite was
first discovered at a place called
Magnesia. The substances having the
property of attracting iron are now known
as magnets.  This is how the story goes.
In any case, people now have
discovered that certain rocks have the
property of attracting pieces of iron. They
also found that small pieces of these
rocks have some special properties.
They named these naturally occurring
materials magnets. Later on the process
of making magnets from pieces of iron
was discovered. These are known as
artificial magnets. Nowadays artificial
magnets are prepared in different
shapes. For example, bar magnet, horse-
shoe magnet, cylindrical or a ball-ended
magnet. Fig.10.4 shows a few such
magnets.
Activity 1
Take a plastic or a paper cup. Fix it on a
stand with the help of a clamp as shown
in Fig. 10.5. Place a magnet inside the
cup and cover it with a paper so that
the magnet is not visible. Attach a
thread to a clip made of iron. Fix the
other end of the thread at the base of
the stand. (Mind you, the trick involved
here, is to keep the length of the thread
sufficiently short.) Bring the clip near
the base of the cup. The clip is raised in
air without support, like a kite.
Fig. 10.4 Magnets of different shapes
Fig.10.3  A natural magnet on a hillside!
Fig. 10.5  Effect of magnet - a paper clip
hanging in air!
Rationalised 2023-24
106 SCIENCE
10.1 MAGNETIC AND NON-MAGNETIC
MATERIALS
Activity 2
Let us walk in the footsteps of Magnes.
Only, this time, we will change the
positions of the magnet and the iron.
There will be a magnet at the end of our
shepherd's stick. We can attach a small
magnet to a hockey stick, walking stick
or a cricket wicket with a tape or some
glue. Let us now go out on a "Magnes
walk" through the school playground.
What does our "Magnes stick" pick up
from the school ground? What about
objects in the classroom?
Collect various objects of day-to-day
use from your surroundings.  Test these
with the "Magnes stick". You can also
take a magnet, touch these objects with
it and observe which objects stick to the
magnet. Prepare a table in your
notebook as shown in Table 10.1. and
record your observations.
Look at the last column of Table 10.1
and note the objects that are attracted
by a magnet. Now, make a list of
materials from which these objects are
made. Is there any material common in
all the objects that were attracted by
the magnet?
We understand that magnet
attracts certain materials whereas some
do not get attracted towards magnet.
The materials which get attracted
towards a magnet are magnetic – for
example, iron, nickel or cobalt.  The
materials which are not attracted
towards a magnet are non-magnetic.
What materials did you find to be non-
magnetic from Table 10.1? Is soil a
magnetic or a non-magnetic material?
Table 10.1 Finding the objects attracted by magnet
Boojho has this question for you.
A tailor was stitching buttons on
his shirt.  The needle has slipped
from his hand on to the floor.
Can you help the tailor to
find the needle?
f o e m a N
t c e j b o e h t
f o e d a m s i t c e j b o e h t h c i h w l a i r e t a M
/ d o o w / m u i n i m u l a / c i t s a l p / h t o l C (
r e h t o y n a / n o r i / s s a l g
s e n g a M y b d e t c a r t t A
t e n g a m / k c i t s
) o N / s e Y (
l l a b n o r I n o r I s e Y
e l a c S c i t s a l P o N
e o h S r e h t a e L ?
Rationalised 2023-24
107 FUN WITH MAGNETS
If you fill this table and send it to
Paheli and Boojho, they can compare
the amount of iron filings found in soil
from different parts of the country. They
can share this information with you.
10.2 POLES OF MAGNET
We observed that iron filings (if they are
present) stick to a magnet rubbed in the
soil. Did you observe anything special
about the way they stick to the magnet?
Activity 4
Spread some iron filings on a sheet of
paper.  Now, place a bar magnet on this
sheet. What do you observe?  Do the iron
filings stick all over the magnet?  Do you
observe that more iron filings get attracted
to some parts of the magnet than others
(Fig. 10.7)? Remove the iron filings
sticking to the magnet and repeat the
Activity 3
Rub a magnet in the sand or soil.   Pull
out the magnet. Are there some particles
of sand or soil sticking to the magnet?
Now, gently shake the magnet to remove
the particles of sand or soil. Are some
particles still sticking to it? These might
be small pieces of iron (iron filings)
picked up from the soil.
Through such an activity, we can
find out whether the soil or sand from a
given place contains particles that have
iron. Try this activity near your home,
school or the places you visit on your
holidays. Does the magnet with iron
filings sticking to it, look like any one
of those shown in Fig. 10.6?
 Make  a table of what you find.
Fig. 10.6 Magnet with (a) many iron filings
(b) few iron filings and
(c) no iron filings sticking to it.
(a)
(b)
(c)
Table 10.2 Magnet rubbed in sand.
How many iron filings?
n o i t a c o l f o e m a N
d n a y n o l o C (
/ y t i c / n w o t
) e g a l l i v
n o r i d n i f u o y d i D
o t g n i k c i t s s g n i l i f
? t e n g a m e h t
/ w e f y r e v / y n a M (
) e n o n
activity. Do you observe any change in
the pattern with which the iron filings
get attracted by different parts of the
magnet? You can do this activity using
pins or iron nails in place of iron filings
and also with magnets of different shapes.
Draw a diagram to show the way iron
filings stick to the magnet. Is your drawing
similar to that shown in Fig. 10.6 (a)?
We find that the iron filings are
attracted more towards the region close
Fig. 10.7 Iron filings sticking to a bar magnet
Rationalised 2023-24
108 SCIENCE
to two ends of a bar magnet. Poles of a
magnet are said to be near these ends.
Try and bring a few magnets of different
shapes to the classroom. Check for the
location of the poles on these magnets
using iron filings. Can you now mark the
location of poles in the kind of magnets
shown in Fig. 10.4?
10.3 FINDING DIRECTIONS
Magnets were known to people from
ancient times. Many properties of
magnets were also known to them. You
might have read many interesting
stories about the uses of magnets. One
such story is about an emperor in China
named Hoang Ti. It is said that he had
a chariot with a statue of a lady that
could rotate in any direction. It had an
extended arm as if it was showing the
way (Fig. 10.8). The statue had an
interesting property.  It would rest in
such a position that its extended arm
always pointed towards South. By
looking at the extended arm of the
statue, the Emperor was able to locate
directions when he went to new places
on his chariot.
Let us make such a direction finder
for ourselves.
Activity 5
Take a bar magnet.  Put a mark on one
of its ends for identification. Now, tie a
thread at the middle of the magnet so
that you may suspend it from a wooden
stand (Fig. 10.9). Make sure that the
magnet can rotate freely. Let it come to
rest.  Mark two points on the ground to
show the position of the ends of the
magnet when it comes to rest. Draw a
Paheli has this puzzle for you.
You are given two identical bars
which look as if they might be
made of iron. One of them is a
magnet, while the other is a
simple iron bar. How will
you find out, which one
is a magnet?
Fig. 10.8  The chariot with direction finding statue
Fig. 10.9 A freely suspended bar magnet
always comes to rest in the same direction
Rationalised 2023-24
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FAQs on NCERT Textbook: Fun with Magnets - Science & Technology for UPSC CSE

1. What are magnets and how do they work?
Ans. Magnets are objects that produce a magnetic field, which is a force that can attract or repel certain materials. They work based on the alignment of their atoms, which creates a magnetic field. When a magnet comes in contact with certain materials, such as iron or steel, these materials become temporarily magnetized and are either attracted or repelled by the magnet.
2. What are the different types of magnets?
Ans. There are three main types of magnets: permanent magnets, temporary magnets, and electromagnets. Permanent magnets are made of materials like iron, nickel, and cobalt, and they retain their magnetism even without an external magnetic field. Temporary magnets, on the other hand, only exhibit magnetism when they are in the presence of a magnetic field. Electromagnets are created by passing an electric current through a coil of wire, and their magnetism can be controlled by varying the current.
3. How can I test if an object is magnetic?
Ans. To test if an object is magnetic, you can use a magnet and see if the object is attracted to it. If the object is attracted to the magnet, it is likely magnetic. You can also try to induce magnetism in the object by rubbing it against a magnet several times in the same direction. If the object becomes magnetized and can attract small metallic objects, it is magnetic.
4. Can magnets lose their magnetism?
Ans. Yes, magnets can lose their magnetism over time. This can happen due to various factors such as exposure to high temperatures, strong magnetic fields in the opposite direction, or physical damage. Permanent magnets are more resistant to losing their magnetism compared to temporary magnets. However, even permanent magnets can gradually lose their magnetism over an extended period.
5. How are magnets used in everyday life?
Ans. Magnets have numerous applications in everyday life. They are used in various electrical devices such as speakers, headphones, and electric motors. Magnets are also used in medical imaging machines like MRI scanners, where they help generate a magnetic field to produce detailed images of the body. Additionally, magnets are used in industries for separating magnetic materials, in magnetic door catches, and even in simple household items like refrigerator magnets.
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