# The Effect of Increasing Number of Turns in a Coil on an Electromagnet It Is Capable of Holding

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The Effect of Increasing Number of Turns in a Coil on an Electromagnet It Is Capable of Holding

Introduction

In this investigation I aim to find out what effect increasing the
number of turns in a coil on an electromagnet will have on the
strength of the electromagnet, and the weight it is capable of
holding. I predict that the higher the number of turns there is on
the core the higher the amount of weight the magnet will hold. Also I
predict that, if I double the amount of turns in the coil on the core,
the magnetic field strength of the electromagnet will also double, I
will find out if this is true from the weight it is capable of
holding.

E.g.) 20 turns will hold 50 grams

40 turns I predict will therefore hold 100 grams

Above is a predicted example of what I think might happen when I
increase the numbers of turns in a coil on an electromagnet. I do not
know that twenty turns will hold fifty grams, as this is just an
estimated amount.

Theory
------

In a piece of iron there are millions of tiny ‘atomic magnets’, they
are called this because in each atomic magnet there is a North and a
South Pole. In the piece of iron these tiny atomic magnets line up
with each other in small groups, when they do this they become
domains. In a piece of iron, that is unmagnetised, the domains will
all point in different directions, see diagram 1 below, the domains
are shown by small arrows, the arrowhead indicates the North Pole. As
all the domains are pointing in different directions there will be no
true north seeking or south-seeking pole in the piece of iron as the
domains will cancel each other out, therefore the piece of iron will
remain unmagnetised.

[IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE][IMAGE]But,
when the piece of iron becomes magnetised, the tiny domains will all
turn to point the same direction.

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### Related Searches

This will give the piece of iron a
true north-seeking pole and a true south-seeking pole; the piece of
iron will have become a magnet. To achieve this magnetism the North
Pole of another magnet needs to be stroked along the length of the
piece of iron. This causes the domains to be pulled by the magnetic
force into place so they are pointing the same direction. See diagram
2 below.

[IMAGE]

1. Unmagnetised

Iron

2. Magnetised

Iron

In conclusion to this theory I believe that if I were to break a
magnetized piece of iron in half I would find that either piece of the
magnetic iron would still act as a magnet. This is because all the
domains that are inside the iron would still be pointing in the same
direction as they were before the break. This means there will be an
even number of south-seeking poles to north-seeking poles; it will
still remain a magnet.

For my experiment I will be making a magnet, not by stroking it but by
passing an electric current through its magnetic field, this process
works in a slightly different way. One turn of wire acts like a
magnet, once it is linked up with a battery and has a current flowing
through it, the single turn will have a magnetic field. This can be
proven by passing a turn of wire through a piece of card, then
sprinkling iron fillings on the card, once the current flows though
the wire the iron filings will show the shape of the wire’s magnetic
field. The field shape is very spaced out, weak and in large circles,
it would take a very long time for this to magnetize a core. A
compass can be used to find the direction of the field.

Then I would change the shape of the single turn to a long, thin, and
compact coil, which is also known as a solenoid. I would now repeat
the above experiment with the iron fillings, from this I can see that
the shape of the magnetic field is very familiar, as it is the same as
the one of a bar magnet. I would also notice that inside the solenoid
the magnetic field would be very strong and uniform, the field is more
in tight ovals rather than widely spaced circles, it is this field
that magnetizes a piece of iron when it is placed inside the
solenoid.

One end of the solenoid will act as a North Pole, the other a South
Pole we can find this when we put a small magnet inside the solenoid,
as it will point north. When the soft iron bar is placed inside the
solenoid it will make the magnetic field stronger and larger;
consequently it will enable the magnet to hold a larger weight than
before. This happens because the solenoid has the same effect to the
piece of metal as a magnet does when it strokes the metal. The
domains in the piece of iron will therefore line up and point the same
direction causing the piece of metal to become magnetized; hence the
new magnet has a magnetic field around it, as does the solenoid.
These forces combine and together they make the magnet stronger.

The magnetization of the core reaches saturation once all the domains
are completely aligned and an increase in current or turns in the coil
at this point would have very little further effect. When the current
is switched off the core retains a very weak residual magnetism.

It is this that I will be investigating in my experiment. I will be
finding out if the number of coils has any effect on the strength of
the magnetic field of my magnet when I test it with weights. From the
scientific knowledge above, I have already proved that the more coils
there are and the closer they are together the larger the magnetic
field strength. Therefore my prediction that the strength of the
magnet doubles as the number of turns on the core doubles, I feel is
probably correct.

Pretest

Aim

The aim of my pretest is to find a suitable current and starting
number of turns on an electromagnet to be used in my main experiment.
The aim for my main experiment is, does the number of turns on an
electromagnet affect the field strength and the weight it is capable
of holding?

Apparatus

· U-shaped soft iron core

· 8 meters of wire

· Power pack

· Ammeter

· Wire cutters and strippers

· Clamp stand

· 10g and 100g weights

· Nail

· 2 crocodile clips

Diagram

Method

· Set up all apparatus as shown in the diagram on the previous page.

· Firstly, I will set the ammeter at 1A with only ten turns on the
electromagnet, then using weights I will measure how much the
electromagnet can hold and then record this result in a table.

· Still with only ten turns on the electromagnet I will increase the
current to 2A. Again by hanging weights from the magnet I will find
out how much it can hold, I will record this result in my table

· I shall now do the same again for 3A

· Now, I shall increase the number of turns to twenty, I will now test
how much the electromagnet can hold at 1A, 2A and 3A, all the results
that I receive I will record in the table.

· Again, I shall increase the number of turns to thirty; I will now
test how much the electromagnet can hold at 1A, 2A and 3A, all the
results that I receive I will record in the table.

Table of Results

Number of turns

Current (Amps)

on the coil

1A

2A

3A

10

0g

0g

50g

20

0g

40g

70g

30

30g

80g

150g

The table above shows the current and the number of turns I have
used. The weights in the middle show how strong the electromagnet was
in grams.

From this information I have decided to use 3A as the current in my
main experiment. This is because I feel 1A and 2A are too low to get
accurate results. 3A is perfect as it is strong enough to get good
and accurate results and it is also not too hot to melt the wire as
any amount larger than 3A could. This is why I did not try 4A and
above as I did not want the wire to burn out and cause any accidents.

I will also start the main experiment at 20 turns on the
electromagnet. This is because; as we can see from out pretest that
it is the lowest amount of turns which will holds a steady amount. I
did not want to start at 10 turns, as it is unpredictable that the
coil would have any affect on the soft iron core and I would
definitely get a result. The range I will use in the main experiment
starts from 20 turns and ends at 100 turns, I will be going up in tens
this will give me nine results. Nine results enable me to plot a
successful graph, find any patterns that may emerge and also find any
anomalous results.

I will measure the strength of the electromagnet by placing a nail
across the ends of the u-shaped iron core. Then I will hang the
weights from this. I will do this experiment three times, therefor
for each number of turns there are on the electromagnet I will gain
three results showing how much it can hold. This will give me
accurate and reliable results, which I will subtract the anomalies
from.

The only variables that will change as the experiment goes are, the
number of turns on the electromagnet, this is because I will be
testing the effect these have on the electromagnet. The other is the
amount of weights I will put on the electromagnet; these will change
because I will be adding more to find the weight the magnet is capable
of holding. All of the other factors that could be variables if I
wanted them to be will be kept the same throughout the main
experiment. These factors are:

· Same soft iron core

· Same length of wire

· Same current of 3A

· Same nail

· Same method of measuring the strength of the magnet

· Same temperature

· Same method of putting the weights on the magnet

· Same amount of area covered by turns

I have expressed these factors more fully in the main method under the

Main Method

Apparatus

· U-shaped soft iron core

· 8 meters of wire

· Power pack

· Ammeter

· Wire cutters and strippers

· Clamp stand

· 10g and 100g weights

· Nail

· 2 crocodile clips

Diagram

Step by step instructions

· Set up all apparatus as shown on the previous page in the diagram.
Make sure to only have 20 turns on the coil and have the ammeter set

· Place a nail to the top of the u-shaped core, it should be held in
place, as the core will be magnetic.

· Using ten-gram weights and a hook, I will hang them off the nail. I
will carry on placing weights on the nail until the magnet is unable
to hold them any more. At this point the weights should drop off the
magnet, as they are too heavy.

· Then I will record this weight in a table.

· Then I will release the core from the clamp and wrap ten more turns
around the core, I must keep the ammeter reading 3A at all times.
Again I will hang weights off the nail, and record the total weight
that the magnet is capable of holding.

· I will carry on adding ten turns to the coil until I have 100 turns
in the coil, every time I get a result I will record it in my table.

· To achieve accurate and reliable results I will repeat the whole
experiment twice again so I will have obtained three results for each
number of coils on the electromagnet.

Variables

These are the only factors that I will be changing throughout my
experiment, the factors I will keep the same I have stated in my fair
test. The only changes that I will be making to the experiment is the
number of coils on the core, I will do this by taking the
electromagnet out of the clamps and wrapping ten more turns on to it,
and then replacing it. I will also have to change the weight that I
put on the electromagnet; I will have to keep adding ten grams until
the nail falls off the magnet. I will do this because it will find
the strength of the electromagnet.

Range

As I am only finding out what effect the number of coils has on an
electromagnet, I will not be changing the current that I use,
therefore I will keep this at 3A at all times. I found out this range
from my pretest, I wanted to go up in 10s so there is a large enough
difference between results and not too large difference, as I don’t
want the magnet to become fully magnetized too soon. In my opinion
nine results is enough to plot a good graph and to find a general
pattern. I didn’t start at 10 turns as this didn’t hold any weights,
I didn’t want to go any more than 100 as I found the coil was getting
too hot and could burn out. The range that I will be using for my
experiment is:

Number of turns

20

30

40

50

60

70

80

90

100

Fair Test

In my experiment I will keep these variables the same in order to keep
my experiment fair. If I changed any one of these factors throughout
my experiment I would find that it changes my results and the
experiment is no longer a fair test.

· I will use the same piece of wire to create the turns in the coil so
that the thickness and length will not change. If either of these
factors was to change there may be an increase in resistance this
could decrease the strength of the electromagnet, therefore a weaker
magnet is produced.

· I will use the same nail because different nails might be attracted
to magnets easier than other nails. A rusty nail will not be as
attracted as a clean, shiny one would be.

· I will use the same u-shaped core in my experiment so that the size
does not change. A large core would take loner to magnetize than a
small one and might also hold more than a small core; therefore we
would get different and unfair results. I will use an iron core
because this magnetizes and demagnetizes quickly, whereas steel takes
time and would not give me accurate results.

· I will have to use the same method of measuring the magnetic force
of the magnet I have decided to use ten-gram weights because weights
would give me an answer in grams straight away; a Newton meter would
give an answer in Newton’s. This is not a problem as I could easily
use a conversion graph to convert my results; although with a Newton
meter you must read off the strength very quickly and can easily been
mistaken therefore I will use weights in my experiment, as it is more
reliable.

· I will keep the current the same as I am only testing to find the
effect the number of coils has on an electromagnet. The current must
not be too low as the results would be inaccurate but not too high as
it might trip the power pack and burn out the wire. I will use 3A; I
found this from my pretest results.

· I will try to keep the coil of wire at the same temperature
throughout, as I do not want the wire to burn and melt its plastic
coating, as this is dangerous. I will do this by allowing a cool down
period where I will turn off the current and leave it for a few
minutes. It will be impossible for me to keep the temperature exactly
the same at all times but I feel that the temperature will not affect
my results greatly.

· Another important factor I will keep the same is the method I put
the weights on the electromagnet, if I put them all on gently instead
of dropping them on I will find that my results will be much more
accurate. I will also I will also add ten gram weights not 100, as
ten grams is much more precise.

· I must also try to keep the area that the turns on the electromagnet
at the same size throughout, by doing this it will ensure that the
concentration of magnetic fields stays the same. I need to do this as
more concentrated turns will provide more strength to the
electromagnet.

Reliability

In my experiment I need to know that my results are reliable and
correct. To do this I will need to repeat my experiment three times,
so for every time I add ten coils I will test to find out how much the
electromagnet can hold, I will test it three times. In my opinion I
think it would be best to do one whole experiment and add ten turns
each time and then go back to the beginning again, rather than
measuring each ten turns three times. I think this will make my
results fair and more accurate.

Accuracy

I will find out if my results are accurate by looking at the
difference of weight between each result, I am referring to all three
results taken for example at twenty turns. I will know if my results
are accurate as they will be close together, similar or even
identical. If results are identical then I know that there are more
than likely to be correct, it would be very unusual if three results
were almost the same and all to be wrong. By following the fair test
values I hope to find that my results are close together and very
accurate.

Analysis – Table of Results

Anomalous results

Number of Turns

Weight

Held (g)

in the coil

Experiment 1

Experiment 2

Experiment3

Average

20

50

60

50

53

30

200

80

100

90

40

110

120

130

120

50

210

180

190

193

60

220

230

240

230

70

360

320

340

340

80

400

410

420

410

90

450

490

460

467

100

540

580

560

560

Graphs and Tables Analysis

As you have just seen I have produced a table of results and two
graphs. My table shows the range of the number of turns I have used,
the results I obtained from my three experiments and it also shows an
average that I have worked out. My table shows any anomalous results
that I have subtracted from my average, this will keep my results
accurate. On my first graph I have shown all three results I have
obtained for each ten turns that I added, this makes it much easier to
find any anomalies, which I have circled. My second graph shows all
the averages of the three results for each ten turns; in this graph I
have subtracted the anomalies. For each graph I have added a curved
line of best fit, this shows the general sequence of the weight that
an electromagnet can hold. It also helps if I wanted to find out how
much an electromagnet would hold with 35 turns for example, I would
simply be able to read this information off my graph and I would find
it could hold 95 grams.

I predicted that my graph would be a straight-line graph, I have
looked at my graph of averages and I have added a line of best fit. I
have done this freehand; therefore; the line of best fit is a curve.
The line is, although it is not shown on the graph starts at the
origin and becomes very shallow at the start, I feel it I shallow
because the magnetism was not strong enough to start with and was
having no affect on the domains. It begins to increase in gradient
and later becomes very steep or proportional and continues this
pattern until I stopped investigating. This shows that the iron core
starts to magnetize slowly and will not hold a large force when there
is a small coil around the core. Its field strength increases when
the coil grows larger; it is now able to hold a larger force. From my
graph of averages I feel that the weight held for 60 turns was too low
and should be slightly higher, this is something I could assess again
if I was to repeat the experiment.

I feel I have received these results because, in a piece of iron that
is unmagnetised, the domains will all point in different directions.
As they are doing this there is no true north seeking or south-seeking
pole in the piece of iron as the domains cancel each other out,
therefore the piece of iron will remain unmagnetised. But, when I
magnetized the piece of iron, the tiny domains turned to point the
same direction. This will give the piece of iron a true north-seeking
pole and a true south-seeking pole; the piece of iron will have become
a magnet. But I stopped my experiment before all the domains had
chance to point in the same direction, if they were to have done I
could say my magnet had saturated. Because I stopped I never knew
when my magnet would have saturated, to find this I will need to
extend my range, I predict that once the magnet saturated I feel the
line of best fit on my graph would curve and then continue at a
horizontal line.

In my experiment I have made a magnet, not by stroking it with another
magnet, but by passing an electric current through its magnetic
field. This process works in a slightly different way, but still
causes the domains to be pulled by the magnetic force into place so
they are pointing the same direction. One turn of wire acts like a
magnet, once it is linked up with a battery and has a current flowing
through it, the single turn will have a magnetic field. The wire’s
magnetic field shape is very spaced out, weak and in large circles, it
would take a very long time for this to magnetize a core. For my
experiment I changed the shape of the single turn to a long, thin, and
compact coil, which is known as a solenoid. I have noticed that
inside the solenoid the magnetic field is very strong and uniform, the
field is more in tight ovals rather than widely spaced circles, it is
this field that magnetizes a piece of iron when it was placed inside
the solenoid.

One end of the solenoid acted as a North Pole, the other a South
Pole. When the iron bar is placed inside the solenoid it will make
the magnetic field stronger and larger; consequently it enables the
magnet to hold a larger weight than before. This happens because the
solenoid has the same effect to the piece of metal as a magnet does
when it strokes the metal. The domains in the piece of metal will
therefore line up and point the same direction causing the piece of
metal to become magnetized; hence the new magnet has a magnetic field
around it, as does the solenoid. These forces combined and together

This is how I received my results, my results from the graph and the
theory link and show me that the more coils there are on an
electromagnet the stronger it will be. This theory is true but only
until the magnetism of the core reaches saturation when all the
domains are completely aligned, at this point an increase in current
or the number of coils would make no difference or have little further
effect. This would be shown on the graph as a straight horizontal
line. It is clear that from my results that my electromagnet was no
way near saturation and if I had carried on increasing the number of
coils I would have found that eventually my graph would have
straightened out.

In conclusion to this, I predicted that the higher number of turns
there is on the core the higher the amount of weight the magnet will
hold, I have come to the conclusion that this is correct as I have
stated in the above paragraph and in my theory. Also I predicted
that, if I doubled the amount of turns in the coil on the core, the
strength of the electromagnet will also double, I would then find out
if this was true from the weight it was capable of holding.

E.g.) 20 turns will hold 50 grams

40 turns I predict will therefore hold 100 grams

Above is what I thought might happen when I increased the number of
turns in a coil on an electromagnet. When I predicted this I did not
know that twenty turns would hold fifty grams, as this was just an
estimated amount. From my experiment my results concluded that this
was not true, I found that the doubled number of coils far exceeded
its predicted amount of weight it was possible of holding.

E.g.) 20 turns on average held 53 grams whereas

40 turns on average held 120 grams.

If this experiment had followed my prediction 40 turns would have held
106 grams. This one example is although very close to the predicted
amount, it is not exact. Yet further down my table of results I found
a much larger gap between the two results.

E.g.) 50 turns on average held 193 grams whereas

100 turns on average held 560 grams

Here there is a large gap of 174 grams, if my results matched my
prediction this gap would not be here. I feel this is because an
electromagnet has a compound effect on the field strength when more
coils are added; this makes it difficult to establish the exact
relationship between the number of coils and the magnetic field
strength.

Evaluation

Accuracy

I feel that from my experiment, the results that I received were very
accurate and all followed an obvious pattern. I think that the
results were very good as they all were very similar and close
together, in my opinion, this was because I tested each number of
coils three times each. If results are close together, similar or
identical then this shows that they are clear and truthful answers,
they are very possible to be correct. It was very rare that results
differed more that 30g away from each other. This shows me that the
results I was getting were very accurate as it would be very unlikely
for me to get three results which all proved to be wrong. An example
of my results are, for 20 turns, the results gained were 50, 60 and
50, these all very in close proximity. Another way than just looking
at a table to see if the results are close and clear, is to look at
the graph I produced, as you can see the results I have plotted follow
a clear pattern, a smooth curve that straightens out, my results
accurately inhabit a line of best fit. I feel this has happened due
to the fact I kept to my fair testing rules throughout. If I was to
improve to make my results more accurate I would extend my range, see
experimental procedures on the next page.

Anomalous Results

These are also know as pattern breakers as they will fall out of
pattern with other results I have gained. In my experiment I only
found one anomalous result, this individual was much higher than the
results I gained in the two other tests and also what was expected. I
feel this happened because I might have not checked that the variables
were not set correctly, such as the current was higher than 3V, also
the number of coils could also have been higher due to carelessness or
I did not follow a fair test value, which are all ment to be kept the
same at all times, as carefully as I should have done. I feel that
the sudden increase in strength of the electromagnet was due to
temperature, the rise in temperature came from the wires getting hot,
the rise will have caused this sudden surge in energy.

Reliability

From my results I feel that they were good enough to support a firm
conclusion, from these I agree that I was wrong in my prediction to
state that as the number of coils doubled so did the weight the
electromagnet could hold. From the results I was gaining I could
easily see that the numbers were not following the pattern I had
predicted

E.g.) 50 turns on average held 193 grams whereas

100 turns on average held 560 grams

Instead, I conclude that I know that an electromagnet has a compound
effect on the field strength when more coils are added; this makes it
difficult to establish the exact relationship between the number of
coils and the magnetic field strength. Although by using my graph I
could predict how many coils I would need to hold 350grams, 75 is the
answer, there is no pattern, such as the one I predicted, between 75
turns and 350grams but from looking at my graph it is easy to
establish any values needed. I feel my results strongly reflect and
support my conclusion.

Experimental Procedure

I personally feel that my experimental procedure was excellent as I
stuck to the fair test values that helped me produce accurate and
reliable results. Although the method I used to find out the results,
how much the electromagnet could hold, was not as reliable as I would
have hoped. Instead of ten-gram weights, I could have used drawing
pines or paperclips; by doing this I would have gained more concise
results and the strength to a more accurate number or weight. Another
way I could have improved my readings, the strength to a more accurate
number, would to place an iron bar on a pair of scales then increase
the strength of the electromagnet by adding more coils an investigate
to see if the iron bar gets lighter. I agree it would, as the force
of the electromagnet will cause it to do so, by using this method I
would gain exact numbers and my results would be more accurate.

If I had decided to look at the magnetic field strength instead of the
electromagnet strength I could have used a compass, I would move the
compass at shot distances away from the electromagnet until the
compass was first effected by the magnet If I was to keep the same
method I would pay more attention to the temperature and try keep it
the same throughout my experiment as I felt this let me down and
affected my experiments results, I would do this by testing the
temperature of the surrounding area of the electromagnet and only
carry out my experiment when the temperature was within a small,
decided range. I could have put the electromagnet in water but make
sure that all wires were well insulated. I also feel I might not have
paid enough attention to the area that the number of coils covered,
with a small number of coils a smaller surface area of the iron core
was covered than with a lager number of coils, also the more
concentrated the magnetic fields were the more powerful the field
strength. This factor will have definitely affected my results. To
improve my testing I feel I should have marked out an area upon the
iron bar, the wires could only cover this given area even if it meant
the turns to be stacked upon on another.

To improve my experiment I feel I should have expended the range in
two different ways. Both ways would improve my data and gain me a
better understanding of the line of best fit on my graph. I would
this by adding a smaller number of coils each time. Instead of ten I
would go up in fives, this would show in more detail the exact course
the graph takes. The other way would to extend the range, in would
carry going up in tens (or fives) until I found the point when my
electromagnet saturated, all the domains were pointing in the same
direction, in the graph this would be when the line of best fit
flattens to become a horizontal line.

Further work

To further my investigation I would still keep to the same aim, to
find out what effect increasing the number of turns in a coil on an
electromagnet will have on the strength of the electromagnet, and the
weight it is capable of holding, but change certain values to
understand how these effected my results. Firstly I would definitely
extend my range as I have already mentioned in my experimental
procedure. I would add a smaller number of turns each time to my
electromagnet so that my results would be more accurate and also so
that I knew that the line of best fit on my graph was more truthful
and reliable. I would also extend my range so that that I would find
out two different issues. Firstly I would try my electromagnet with
no coils to find out if it had any electromagnetism before I even
started, as this factor would have caused some alterations on my
results. The second would be to extend my range in the opposite
direction, go further than 100 turns, by doing this I would find out
when the magnet saturated, this is when all the tiny domain inside a
magnet has turned to face the same direction, this will be the magnets
greatest strength. As the magnet saturated I would find that the line
of best fit on my graph would become a horizontal line.

I felt the temperature affected my experiments results, as I was not
watching this factor throughout my experiment, as it is very hard to
control. If I was to repeat my experiment I would eliminate the
possibility of the temperature affecting the results, I would do this
by testing the temperature of the surrounding area of the
electromagnet and only carry out my experiment when the temperature
was within a small and decided range. I could put the electromagnet
in a water bath and make sure that all wires were well insulated and
the temperature was not too high, possibly around room temperature. I
would then hang weights from the electromagnet that was still inside
the water bath and record my results. I would have to take into
consideration the fact that the water will reduce the weight of the
ten-gram weights, as the water will have up-thrust.

I could also change the method in which I measured the strength of the
electromagnet; instead of using ten-gram weights I could use drawing
pins or paper clips. These both would give me an exact weight that the
electromagnet was capable of holding. I could use a compass instead
of weights, I would move the compass nearer and a slow speed toward
the electromagnet, I would record the distance from the electromagnet
the compass was when it was affected. This method would not be
suitable for my experiment, as it would not conclude my aim.

To investigate further I would see what affect thicker wires, yet the
same amount of current, had on he electromagnet. I feel that there
possibly would be no affect but I might be wrong, therefore I should
find out. I will also investigate the concentration of the wires, I
think I will find that the smaller the concentration, the area the
wires cover on the soft iron core, the more powerful the electromagnet
will prove to be. I will do this by investigating with the area the
wires cover on the core; I will then test the results I gain three
times each and record then. I shall look for any obvious patterns.