Extended Essay

IB Extended Essay
Evaluating the effect of Automobiles and
Advanced High Strength Steel on the strength
of the Geomagnetic Field
Name: Ethan Dodd
Candidate Number: 001042-0007
School: Prague British School
Centre Number: 001402
Subject: Physics
Word Count: 3936
Number of Pages: 33

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Physics
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Abstract
This essay will evaluate the effect of Automobiles and Advanced High Strength Steel on the strength
of the Geomagnetic Field. The term ‘geomagnetic field’ refers to the magnetic field surrounding
Earth. The low strength of the field makes it susceptible to external influences, like human objects,
such as, vehicles and steel. Advanced High Strength Steel was chosen as the second variable as it is
the most abundant metal in most modern cars. The objective of this essay is to present the findings of
an investigation into the effects these two variables have on the field. The investigation, consisting of
two experiments, was conducted in Prague, Czech Republic. The location was chosen for its distance
from external influences. The recordings were made with a super-charged proton magnetometer and a
magnetic probe, however, anomalies were discovered as the field fluctuated during both experiments.
The field was measured from marked distances away from the object, the vehicle or steel cube. These
findings were then graphed in order to determine whether these two variables had an effect, and
whether they followed the same trend. It was discovered that the larger the mass of the variable, the
weaker the field in that area; the field grew weaker closer to the object. The largest of the vehicles
was able to weaken the field by approximately 2000nT.
Word Count: 220
Acknowledgements
I would like to thank Mr Margerison for being my supervisor and Pavel Hejda, head of the Institute of
Geophysics in Prague, for allowing me to the conduct the experiment with the use of equipment from
the Institute.

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Contents
1. INTRODUCTION………………………………………………………………...…….. 3
1.1 Theories on the source of the geomagnetic field.................................................. 3
1.2 Dynamo Theory.................................................................................................... 5
1.3 Uses of measuring the field................................................................................... 5
2. INVESTIGATION………………………………………………..…..………….…….. 7
2.1 Experiment 1 – Effect of Entire Combustion Vehicle…..…………..….....…… 7
2.1.1 Equipment…………………..………………………....…………….…...... 7
2.1.2 Variables. ……..….....………..….....………..….....………..….....…. 8
2.1.3 Data……..….....………..….....………..….....………..….....………... 8
2.1.4 Evaluation……..….....………..….....………..….....………..….....…. 10
2.1.5 Conclusion……..….....………..….....………..….....………..…......... 11
2.2 Experiment 2 – Effect of Advanced High Strength Steel……..….....…............ 13
2.2.1 Equipment…………………..………………………....…………….…...... 13
2.2.2 Variables. ……..….....………..….....………..….....………..….....…. 13
2.2.3 Method….....………..….....………...…......…......………..….....…... 14
2.2.4 Data……..….....………..….....………..….....………..….....………... 15
2.2.5 Evaluation……..….....………..….....………..….....………..….....…. 17
2.2.6 Conclusion……..….....………..….....………..….....………..…......... 18
3. DISCUSSION……………………………………………………………….....….….... 19
4. APPENDICES……………………………………....………………………….......….. 20
4.1 Appendix I: Experiment 1 – Raw Data.………..….....……… .………… 20
4.2 Appendix II: Experiment 1 – Graphs.………..….....……… .………….... 23
4.3 Appendix III: Experiment 2 – Raw Data.………..….....……… .……….... 26
4.4 Appendix IV: Experiment 2 – Graphs.………..….....……..…....…....…… 29
5. REFERENCES….….………………………………….….………………………...... 32
5.1 Images Cited………………………………………...…..……….....….....…... 32
5.2 Works Cited…………………………………...…..…………..……………… 32

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1. INTRODUCTION
The geomagnetic field is extremely important to life on Earth. The geomagnetic field is often relied
upon for direction when traveling, it also prevents cosmic rays from damaging life on Earth. Birds
use it to navigate when migrating, humans rely on it for the use of compasses. The field is in fact
weaker than a fridge magnet which makes it very susceptible to manipulation. The vitality of the field
means mankind should realise the effects it has on the field, and herein lies the research question;
what is the effect of automobiles and our most commonly used alloy, steel, on the geomagnetic field?
1.1 Theories on the source of the field
If we were to consider Earth only as a large bar magnet it would provide a simple explanation as to
the origin of the magnetic field. It would explain, in simplified terms, why there is a north and south
pole, and why a compass will only point north, unless there is interference. For this, it has to be
assumed that the bar is positioned so that the south end is located where our North Magnetic Pole is.
This ‘bar’ is not positioned in perfect alignment with the poles, it is actually skewed slightly off
centre, as shown in Fig. 1.11
. This skew is called the declination.
Obviously, this analogy is flawed and holds little credibility as a theory; in reality it is much
more complicated as the Earth’s field is not constant like a magnet’s. The mystery behind the
magnetic field is still quite a controversial topic even though it has intrigued mankind since the 13th
century when the first question of how lodestones became magnetised arose. Many different theories
as to why this field is able to exist have been put forward. Some of the most revolutionary are
included here in order to provide a sense of how wrong even modern theories could be.
1. William Gilburt, a physicist of the 16th
century produced one of the first theories concerning
the magnetic field. He used a magnetised sphere, named ‘Terella’, meaning little Earth, and
moved a small compass around it2
. He found that the compass always pointed north-south.
1
Dunbar, Brian. "2012: Magnetic Pole Reversal Happens All The (Geologic) Time." NASA. NASA, 05 Dec. 2011. Web. 09
Sept. 2014.
2
Stern, David P. "The Terrella." The Terrella. David P. Stern and Mauricio Peredo, 25 Nov. 2001. Web.
Fig. 1.1 - Illustration showing the
declination of the two types of
poles.

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He argued that the same thing was happening on a much larger scale on Earth and therefore
that the Earth must be a large magnet.
2. P.M. Blackett, a physicist who won a Nobel Prize for his work on cosmic rays in 1948,
revived the theory that any uncharged solid rotating object was intrinsically magnetised3
. The
theory was based on the idea of ‘gravitational magnetism’ and later became known as the
‘Blackett effect’8, however, the theory was never generally accepted as it was never observed
His theory also wouldn’t account for a magnetic dipole reversal.
3. The Dynamo Effect is the most accepted theory of today. According to Gary Glatzmaier of
the Los Alomos National Laboratory, ‘The typical lifetime of a magnetic field like Earth’s is
several thousand years. The fact that it has existed for billions of years means something
must be regenerating it all the time.’4
The Dynamo Effect is able to explain how the field is
self-sustaining and has not dissipated. The computer model created by Glatzmaier and his
team is the most advanced yet and is considered the most accurate representation of the
Earth’s core, it is so accurate that it switched poles, something that has happened many times
over the past few billion years and is due to happen again soon, see Fig 1.25
. As the model
proved to be so accurate and supports the Dynamo Effect it is accepted by most experts.
3
Stern, David P., Dr. "Origin of The Earth's Magnetism." The Great Magnet, the Earth. Lab. for Extraterrestrial Physics,
Goddard Space Flight Center (NASA), 23 Feb. 2008. Web. July 2014.
4
Glaztmaier, Gary A., and Paul H. Roberts. "WHEN NORTH GOES SOUTH." Projects in Scientific Computing (1996): n. pag.
Psc.edu. Pittsburgh Supercomputing Center. Web. 22 July 2014.
5
Groleau, Rick. "When Our Magnetic Field Flips." PBS. PBS, 18 Nov. 2003. Web.
Fig 1.2 – Illustration from Glatzmaier’s
model showing the magnetic dipole
reversal. Magnetic field lines are blue
where the field is directed inward and
orange where directed outward.
The top image shows the field normally.
The bottom three images show the process
of the pole reversal.
500 years before the middle at the middle of the 500 years after the middle
of a magnetic dipole reversal, reversal, and of the reversal.

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1.2 Dynamo Theory
Dynamo Theory describes the manner in which a convective fluid acts to create and maintain a
magnetic field. When a current is passed through a wire, a magnetic field will form around that wire.
Similarly, an electric current is produced in the wire when passed through a magnetic field. In the
Earth, the liquid metal that makes up the outer core passes through a magnetic field, which causes an
electric current to flow through the metal. The electric current then creates its own field, which is
stronger than the first field. As more liquid metal passes through the second field, more current flows,
which increases the field even further. This self-sustaining loop is known as the geomagnetic
dynamo6
.
There are three requirements for a dynamo to work:
1. A conductive fluid
2. Kinetic Energy
3. Internal energy to drive the convective motions
The first requirement is provided through tidal heating. Tidal forces between celestial orbiting bodies
creates friction that heats up the core of these bodies.
The second requirement is created from the planetary rotation. The Coriolis Effect also plays a role in
sustaining the dynamo. It causes the liquid metal to spiral which forces the fields to align and join
forces. Without this effect, caused by the rotation of the planet, the fields would simply cancel each
other out.
The final requirement comes from the surface of the solid inner core as it releases energy. Material
from the outer core ‘freezes’ onto the inner core, releasing heat as it does so.
When the flow is altered by the Lorentz force it means the magnetic field is strong enough to
influence the fluid motions, which means that the kinematic approximation no longer works.
These nonlinear dynamos are sometimes referred to as hydromagnetic dynamos. Virtually all
dynamos in astrophysics and geophysics are hydromagnetic dynamos. They are simulated
numerically using computers.
1.3 Uses of measuring the field
The ability to measure the strength of the field is extremely useful to developers and
geologists alike. It may hint to the type or usefulness of an area, for example, an area with a weaker
magnetic field may have a vast amount of iron underground. Understanding just how the field works
may save billions in money on searching for various materials as they could simply be found using
measurements of the field. Studying the field is also incredibly important, should we ever lose it. The
Dynamo Effect may be self-sustaining but there are also many concerns as to why the field hasn’t
failed already; if the field does fail, the populous should be prepared. The study of this field may lead
to future discoveries on the sustainability and the options Earth has if it does appear to be weakening.
6

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Furthermore, the fluctuation of the field can have an adverse effect on pipelines, and other
things like this that humanity rely on. In November 2003, during the Halloween magnetic storms, the
pipe-to-soil potential of the DRUZBA and IKL oil pipelines, in Central Bohemia, was recorded and
analysed by the Geophysical Institute in the Czech Republic7
. The fluctuations caused by the storms
created a difference in potential between the soil and the pipelines and induced a current. It was able
to induce a current as the field lines were cutting the conductor as they fluctuated, this follows the
right hand coil rule. The telluric currents alter the potential to a point at which the electrochemical
processes of corrosion can occur. Corroding pipelines could be dangerous to the environment and are
expensive to repair. Although the magnetic storms were much stronger and created more fluctuations,
the fluctuations created by things like automobiles may slowly be corroding pipelines. This could be
relevant when deciding where to build things like motorways or factories.
The focus of this essay will be on how different sizes of automobiles, for example a car and a
van, and Advanced High Strength Steel, affect the geomagnetic field. Advanced High Strength Steel
was chosen as it is the most abundant material found in modern vehicles. The value of studying the
effect of steel on the field is that it may also lead to the discovery of anomalies in the field, such as a
very low strength or a regular fluctuation in strength in certain areas. This information would help to
understand the planet we live on and the natural phenomena that proceed daily across the globe. It
may also help us understand whether the man-made influence humanity has on the Earth, such as the
vast amount of cars, has a long-term effect on the Earth or whether the field is always able to reassert
itself.
7
Hejda, Pavel, and Josef Bochníček. Geomagnetically Induced Pipe-to-soil Voltages in the Czech Oil Pipelines during
October–November 2003. Tech. Prague.: Annales Geophysicae, 2005. Print.

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2. INVESTIGATION
Two experiments were done in this investigation. A preliminary investigation was carried out in
order to determine whether or not we could have an effect on the field. The experiment was then
focused and just one variable was chosen, Advanced High Strength Steel. This was chosen as it is
commonly used in vehicles, but also because it is used in other manufacturing processes. This means
that although this experiment considers vehicles, the results may be applied elsewhere. Both
experiments measure the Magnetic Flux Density.
It is predicted that the larger the car or the greater mass of steel there is present, the weaker the field
will be; there should also be more fluctuations.
2.1 Experiment 1 – Effect of Entire Combustion Vehicle
The magnetic field strength will be measured at 10 different distances from a marked location.
Different vehicles will be placed within that marked location, which should cause a change a
fluctuation in the strength of the field. The field strength will be measured in nanotesla using a super-
charged proton magnetometer. The particular magnetometer used in this experiment is preferred by
magnetic observatories due to its high sensitivity and accuracy compared to alkali vapour and Proton
Precession magnetometers.
Due to the similarity of the two methods, an extended method is included in ‘Experiment 2 – Effect of
Steel’ only.
2.1.1 Equipment
 GSM-19 Overhauser Magnetometer v7.0
Resolution: 0.01 nT 
Absolute Accuracy: +/- 0.1 nT. (An accuracy of ±1nT was used for this investigation)
Dynamic Range: 20,000 to 120,000 nT 
Gradient Tolerance: Over 10,000 nT/m 
Sampling Intervals: 60+, 5, 3, 2, 1, 0.5, 0.2 sec 
Operating Temperature: -40°C to +50°C8
 1 Supercharged Proton Magnetometer
 Škoda Fabia (car)
 Toyota Land Cruiser (4x4)
 Ford Transit Van (van)
 Toyota Tundra (small truck)
8
"Rugged Overhauser Magnetometer." Gem Systems. GEM, n.d. Web. 03 Sept. 2014.

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2.1.2 Variables
Independent: Type of Vehicle
Dependent: Strength of the field at a given distance for a given vehicle
2.1.3 Data
For raw data, please refer to Appendix 1.
Processed Data
Table 1: Table showing mean values for all data in experiment 1
The table contains the raw data but in a processed form. The mean of all four trials for each distance
marker has been calculated.
Distance
(m, ± 1cm)
Field Strength (nT, ± 0.5nT)
No Vehicle Car 4x4 Van Small Truck
20 48 849 48 845 48 842 48 842 48 830
18 48 851 48 854 48 845 48 841 48 831
16 48 850 48 850 48 845 48 839 48 826
14 48 849 48 837 48 842 48 834 48 822
12 48 847 48 840 48 834 48 831 48 813
10 48 846 48 832 48 833 48 824 48 802
8 48 846 48 830 48 824 48 817 48 778
6 48 846 48 819 48 808 48 790 48 638
4 48 842 48 778 48 794 48 564 48 309
2 48 838 48 668 48 521 48 336 47 619
1 48 835 48 794 47 879 47 331 46 939
The uncertainty of the ‘Distance’ is taken from the measuring tape which has a resolution of + 1cm.
The uncertainty of the ‘Field Strength’ is taken from the equipment having a resolution of + 0.5nT.
The percentage uncertainty of this experiment is 0.001%
The percentage uncertainty is calculated using only the first piece of data collected (48 849) using the
following formula:
𝑃𝑒𝑟𝑐𝑒𝑛𝑡𝑎𝑔𝑒 𝑈𝑛𝑐𝑒𝑟𝑡𝑎𝑖𝑛𝑡𝑦 =
𝐸𝑠𝑡𝑖𝑚𝑎𝑡𝑒𝑑 𝑢𝑛𝑐𝑒𝑟𝑡𝑎𝑖𝑛𝑡𝑦
𝑣𝑎𝑙𝑢𝑒
× 100

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The mean of each result was calculated using the standard averaging formula:
∑ 𝑡𝑒𝑠𝑡 𝑣𝑎𝑙𝑢𝑒𝑠
𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑡𝑒𝑠𝑡𝑠
An example calculation is shown here for the values from a distance of 10m with no vehicle present:
48 849 + 48 845 + 48 845 + 48 845
4
= 48 846𝑛𝑇
Graph 1: Graph showing the data from Table 1
Error bars have not been included in this graph as the uncertainty, 0.5nT, is negligible when compared
with values in the 48 000s.
46500
47000
47500
48000
48500
49000
05101520
FieldStrength(nT)
Distance (m)
Field Strength (nT)
No Vehicle
Car
4x4
Van
Small Truck

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2.1.4 Evaluation
When doing any investigation involving the measuring of the Earth’s geomagnetic field there are
usually a large amount of limitations and plenty of room for error. Due to the sensitivity of the field,
any anomalous occurrences, like a solar flare from the sun, can have a large impact on the results
taken. Earth received an X-class solar flare from the Sun (Fig. 2.19
) two days before the data was
collected; an X-class solar flare lies in the strongest strength category. These solar storms will have
influenced the data by creating a more unsettled magnetosphere due to the bombardment of high
energy particles from the flares. An unsettled field will have a great large on the ability the vehicles
had to manipulate the geomagnetic field.
Experiment 1 also had too many variables, and thus was useful for finding a specific variable to use in
Experiment 2. The vehicles were all made of different materials, had different amounts of fuel,
different standing temperatures etc.
The large fluctuations in the field when taking data resulted in great difficulty when recording the
field strength. These were caused by a multitude of different factors, for example, the flare, but in
addition to this was the effect the other vehicles had on the field. In Fig.2.210
, the table shows that a
car can affect the strength of the magnetic field by 1nT from 40m away. Due to the fact that modern
day technologies are able to produce measurements accurate to +0.1nT it is evident that the car would
have to be parked more than twice that distance so as not to affect the field, however, it was only
parked 100m away, with other larger vehicles which would have needed to have been parked even
farther. In order to ensure the prevention of anomalous fluctuations, the vehicles and cubes should
have been placed further away.
9
Wall, Mike. "Sun Unleashes Major Solar Flare at Earth (Video)." Space.com. N.p., 10 Sept. 2014. Web. 22 Sept. 2014.
10
Jankowski, Jerzy, and Christian Sucksdorff. "GUIDE FOR MAGNETIC MEASUREMENTS AND OBSERVATORY PRACTICE."
(1996): 49-50. Print.
Fig. 2.1 – Three images taken from a video
showing the release of the X-class solar flare on
the 10th
of September 2014 at 1:45pm from Active
Region 2158 (marked with the red circle)

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Object ri (m)
Safety Pin 1
Buckle of a Belt 1
Watch 1
Metallic Pen 1
Knife 2
Screwdriver 2
Revolver 3
Hammer 4
Spade 5
Rifle 7
Bicycle 7
Motorcycle 20
Car 40
Bus 80
A calculation can be done to determine the amplitude of the anomaly using the following formula:
(
𝑟𝑖
𝑟
)
3
Where, r is the distance of the object from the measurement and ri is the relevant value from the table.
A calculation for the amplitude of the anomaly caused by the car parked 100m away is as follows:
(
40
100
)
3
= 0.064𝑇
This may seem like a tiny anomaly but when trying to work with instruments that have a degree of
accuracy to + 0.1nT, it has a very large effect on the sensitive readings.
To ensure that the fluctuations are kept at a minimum, the experiment should be conducted at a time
of quiet solar weather and away from any external influences, like railway tracks, pipelines, houses
and even the other equipment.
2.1.5 Conclusion
The results clearly suggest that there is an element of accuracy in the hypothesis. It is true, in this
particular investigation, that the larger the vehicle, the weaker the total strength of the field is. The
field when measured with no vehicle showed a smooth flat line in the change in the strength of the
field, when compared to the change in strength when the vehicles were present. However, when you
look at the graph with only the ‘no vehicle’ data (Appendix 2), it is more evident that there is a change
in the field the closer you get to the marked vehicle location (sloping downward on the graph). As the
test done without the vehicle was done after all the vehicles had driven over the marked vehicle point
to the small field where the vehicles were parked, they may have had an unexpected impact on the
results. This unplanned for result may allude to the fact that the field is unable to correct itself
instantly after it has been altered. This could potentially mean we are causing long-term damage to
Fig. 2.2 – Table showing the distances ri at which
some common objects produce a magnetic field of
1nT. These contain some of the ‘rough estimates’
mentioned earlier.

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the field in some areas by subjecting it to concentrated magnetic influences. However, in this case,
although the field fluctuated close to the marked vehicle point, it still stayed within the accepted
strength range of a still field in the Czech Republic, 48 500 – 49 000 , as shown approximately by the
black dot in Fig. 2.311
.
The data produced with the small car present showed an anomaly. The point measured from the 1m
mark, 48 794, appears to have spiked in strength and thus broken the smooth trend followed by the
other tests. Where the point should have continued to decrease, the strength increases in strength by
126 nT. There are a few reasons why this anomaly could have occurred, however, it is most likely
that a train was passing on the nearby track. The prior downward trend of the car’s slope rules out the
theory that something in the car’s materials was not weakening the field but rather strengthening it.
This is one problem with investigations in this field of physics, it is often extremely difficult to
determine why the data has gone wrong, and whether or not it has actually gone wrong.
The strongest fluctuation from the normal strength was the presence of the small truck. This caused
the field to weaken to 46 939nT + 2nT which is approximately 1500 – 2000nT weaker than the
expected strength. The strength of the field at that point would be more commonly found further
south around Italy.
It is evident that there is an effect on the field and that the larger the vehicle the weaker the field
becomes.
11
World Magnetic Model. Digital image. National Geophysical Data Center. N.p., Jan. 2010. Web. 16 Sept. 2014.
Fig. 2.3 – Image
showing the
intensity (in nT) of
the magnetic field
around the world.

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2.2 Experiment 2 – Effect of Advanced High Strength Steel
This experiment serves as a continuation of the Experiment 1, however, it is more focused. The
experiment considers only one variable, Advanced High Strength Steel. There are many more
variables that could have been chosen though, for example:
 Mass of Plastic
 Volume of Fuel
 Mass of other metals
 Volume of the car
If more experiments were done using different variables, conclusions could be drawn on whether it is
the material, or the mass of the material which influences the field most. This information could help
when deciding what materials to use in manufacturing processes, however, it would take an extensive
amount of time to conduct this experiment on each variable.
2.2.1 Equipment
 Pasco Xplorer GLX
 PASPORT Magnetic Field Sensor
 1kg, 2kg, 3kg, 4kg Advanced High Strength Steel cubes (used in vehicles)
 Metre Rule
 Distance Markers
2.2.2 Variables
Independent: Block Mass ± 1 10−3
𝑘𝑔×
Dependent: Strength of the field at a given distance for a given block
Control Variables
 Location – the experiment will be done in an old geophysics lab away from most external
influences, excluding a railway track 8km away.
 Measuring Equipment – the equipment will not change so as to avoid discrepancies in the
data accuracy.
 Type of steel – to ensure that only the mass is influencing the field strength.
 Temperature – the experiment will be done in a single environment over a very short period
of time as temperature affects the strength of magnetic fields.
 Solar Weather – the experiment was done at a time of quiet solar weather so as to avoid any
anomalous fluctuations.

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2.2.3 Method
The method of data collection for both experiments is similar, it is only the scale, equipment and the
independent variable that changes. The method for the second experiment will be described below.
For any investigation measuring the geomagnetic field, either on a professional or on a school scale,
the location is vital when considering the accuracy of the results. The location chosen for this
investigation, Průhonice Botanical Garden, is on the outskirts of Prague in Czech Republic. It is the
site of a group of old geophysics laboratories. The Institute of Geophysics moved to the Czech
mountains, in the 1960’s, as Prague grew and created more disturbances, rendering their data
inaccurate. The site is suitable for small experiments of this size, however, it is not for large
investigations requiring an absolute lack of disturbance on a daily basis. These man-made
disturbances are a problem for geophysics institutes all around the world. The closest source large
enough to influence the results was a railway 8km away from the site, this railway could have caused
the field to fluctuate slightly.
The equipment used in this experiment measures in tesla (T) using a magnetic field probe. The field
was measured without the influence of any steel first in order to produce a control result to which the
other data may be compared.
1) Choose a suitable location and time period
i. The location should contain as few external influences as possible
ii. Data should be taken at a time of quiet solar weather
2) Set up the experiment as shown in Fig. 2.4.
i. For the first test, there should be no cube as it is a control test
ii. Record the field strength every 10cm (results taken from closer will be erratic)
iii. Make sure the markings are accurately placed and are perpendicular to one side of the block
iv. Ensure there are no other cubes within 10m, so as not to disrupt the readings.
3) Set-up the equipment using the following procedure
a. Connect the probe in one of the four slots at the top of the data logger
b. Turn on
Fig. 2.4 – Diagram showing the experiment setup

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c. Press the home button to return to the main menu
d. Using the d-pad select the ‘digits’ function
e. Select the ‘tick’ button and move the cursor over the unit box
f. Select the box and change the units to tesla
4) Start recording the data
i. Start recording from the farthest distance marker (100cm)
ii. Move to each marker and wait 10 seconds before taking a reading
5) Change or place a cube in the assigned location
i. Place the cube so that one edge is on the fixed line
6) Repeat all of the above 5 times and take an average of the results
i. The data should prove more random the closer you are to the cube
2.2.4 Data
For raw data, please refer to appendix 3.
Processed Data
Table 2: Table showing mean values for all data in experiment 2
The values have been converted from tesla into nanotesla.
Distance
(cm, ± 1cm
No Cube 1kg Cube 2kg Cube 3kg Cube 4kg Cube
100 26 890 26 890 26 890 26 889 26 890
90 26 891 26 888 26 887 26 889 26 887
80 26 891 26 887 26 888 26 887 26 886
70 26 891 26 884 26 885 26 885 26 883
60 26 888 26 882 26 881 26 879 26 878
50 26 890 26 879 26 876 26 876 26 875
40 26 885 26 876 26 869 26 866 26 866
30 26 890 26 871 26 865 26 873 26 862
20 26 889 26 866 28 857 26 856 26 852
10 26 891 26 863 26 849 26 844 26 836
The uncertainty of the ‘Distance’ is taken from the metre rule which has a resolution of + 1cm.
The uncertainty of the ‘Field Strength’ is taken from the equipment having a resolution of + 0.5nT.
The percentage uncertainty of this experiment is 0.002%

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Graph 2: Graph showing the data from Table 2
The error bars come from the resolution of the metre rule, ±1m, and the magnetic probe, ±0.5nT.
The error bars on the y-axis are quite low compared to the data, similar to the situation in Experiment
1.
26830
26840
26850
26860
26870
26880
26890
26900
02468101214161820
FieldStrength(nT)
Distance (cm)
Field Strength (nT)
No Cube
1kg Cube
2kg Cube
3kg Cube
4kg Cube

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Graph 3: Graph showing Graph 2 but with ‘Power Trendlines’
The graph above contains the same information as ‘Graph 2’, however, it contains ‘Power
Trendlines’, added using Excel. These trendlines match the data most accurately; the R2
value peaked
at around 0.95, with the ‘3kg’, ‘4kg’, and ‘5kg’ cubes matching this accuracy. A Power trendline is
used when the data sets compare measurements that tend to increase at a specific rate. This means
that the decrease in the strength of the field moves at a steady rate as you move closer to the block.
The measurement with no cube and the’1kg’ cube have a much lower R2
value of 0.007 and 0.63,
respectively. This is most likely due to the anomalies evidently present in the data.
2.2.5 Evaluation
Experiment 2 was able to remove many of the variables present in experiment 1. The steel cubes
focused on one material used in the manufacture of cars. The steel used was specifically Advanced
High Strength Steel as this is the most abundant metal used in modern day automobiles. The steel
cubes were borrowed from a local construction company that also uses the material in the
manufacture of buildings. The experiment was also done inside one of the old geophysics labs at
Průhonice which meant that the temperature was controlled; allowing the steel cubes to uphold a
continuous level of effect.
The equipment used to do the experiment was highly inaccurate. From the previous experiment,
using credible equipment, the field had a strength of around 48 800nT. The field recorded by the
R² = 0.63
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26870
26880
26890
26900
05101520
FieldStrength(nT)
Distance (cm)
Field Strength (nT)
No Cube
1kg Cube
2kg Cube
3kg Cube
4kg Cube
Power (No Cube)
Power (1kg Cube)
Power (2kg Cube)
Power (3kg Cube)
Power (4kg Cube)

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Physics
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school equipment produced a strength of 22 000nT, however, although the numbers are incorrect, the
rate of change should still be accurate. In order to determine whether this is true, the experiment
would have to be done with more accurate equipment. The data produced in this experiment matches
the field strength of that in Colombia in South America.
This experiment will still have been subjected to any solar weather, although it was quiet at the time
of the data collection, and any other external influences which could not be measured.
Geophysics observatories around the world collect years and years of the same data in order to rule
out any chance of the anomalies mentioned above. This could not be done in this investigation which
mean that any anomalies can’t be cancelled out by a vast amount of data. Many more trials would
have been necessary to do this.
2.2.6 Conclusion
Experiment 2 produced a graph identical to experiment 1. It further confirms the theory that the
larger the car or the more steel contained within it, the larger the effect on the field.
The data generally shows that as the size of a vehicle increases, the greater impact it has on the field.
There are more evident anomalies in this experiment, for example when the 1kg cube is present,
however, these are most likely caused by the equipment used to record the data.

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Ethan Dodd
Physics
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3. DISCUSSION
The research conducted for this paper provided strong evidence that the field is being affected by
humanity. The presence of something as insignificant as just one small truck caused the field to
weaken to 46 939. If this is the power just one vehicle has to influence the field, then many vehicles
and the vast number of buildings may be causing fluctuations which could prove detrimental in the
future. Geomagnetic storms are able to corrode pipelines in the Czech Republic. It is likely that the
fluctuations caused by mankind also have a negative effect on the field that we have not yet
discovered.

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Ethan Dodd
Physics
20 | P a g e
4. APPENDICES
4.1 Appendix I
Raw Data from Experiment 1
Table A: Data with no vehicle present
Distance
(m, ± 1cm)
1 2 3 4
20 48 846 48 850 48 851 48 851
18 48 850 48 851 48 851 48 851
16 48 851 48 850 48 850 48 849
14 48 849 48 849 48 848 48 848
12 48 847 48 849 48 845 48 845
10 48 849 48 845 48 845 48 845
8 48 843 48 844 48 844 48 845
6 48 843 48 846 48 847 48 847
4 48 847 48 843 48 839 48 838
2 48 837 48 839 48 837 48 837
1 48 831 48 835 48 836 48 839
Table B: Data with the Škoda Fabia (car) present
Distance
(m, ± 1cm)
1 2 3 4
20 48 847 48 845 48 847 48 841
18 48 852 48 853 48 855 48 854
16 48 851 48 851 48 850 48 847
14 48 837 48 837 48 835 48 837
12 48 840 48 839 48 841 48 839
10 48 834 48 831 48 832 48 832
8 48 831 48 829 48 829 48 831
6 48 821 48 817 48 819 48 819
4 48 782 48 777 48 776 48 776
2 48 666 48 666 48 669 48 669
1 48 773 48 795 48 800 48 809

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Physics
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Table C: Data with the Toyota Land Cruiser (4x4) present
Distance
(m, ± 1cm)
1 2 3 4
20 48 841 48 844 48 843 48 841
18 48 844 48 844 48 846 48 845
16 48 844 48 847 48 844 48 844
14 48 841 48 843 48 842 48 840
12 48 835 48 833 48 834 48 833
10 48 832 48 832 48 834 48 835
8 48 826 48 824 48 823 48 823
6 48 811 48 807 48 807 48 806
4 48 755 48 743 48 840 48 837
2 48 620 48 491 48 488 48 486
1 48 156 47 767 47 785 47 806
Table D: Data with the Ford Transit Van (van) present
Distance
(m, ± 1cm)
1 2 3 4
20 48 842 48 840 48 846 48 840
18 48 839 48 843 48 841 48 841
16 48 839 48 837 48 841 48 840
14 48 833 48 836 48 835 48 833
12 48 829 48 832 48 832 48 831
10 48 825 48 823 48 826 48 822
8 48 816 48 819 48 815 48 817
6 48 793 48 786 48 788 48 791
4 48 626 48 554 48 536 48 539
2 48 462 48 231 48 377 48 274
1 47 379 47 405 47 283 47 257

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Physics
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Table E: Data with the Toyota Tundra (small truck) present
Distance
(m, ± 1cm)
1 2 3 4
20 48 833 48 831 48 829 48 828
18 48 830 48 834 48 829 48 832
16 48 826 48 825 48 827 48 824
14 48 821 48 819 48 825 48 823
12 48 815 48 811 48 813 48 813
10 48 803 48 806 48 797 48 802
8 48 782 48 781 48 777 48 771
6 48 633 48 645 48 639 48 636
4 48 294 48 293 48 341 48 307
2 47 601 47 631 47 628 47 616
1 46 727 47 371 46 851 46 806
All of the uncertainties in this section have derived from the accuracy of the instrument used to take
the measurements and recordings, so a tape measure (+ 1cm) and the Magnetometer (+ 0.5nT).

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Ethan Dodd
Physics
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4.2 Appendix II
This appendix contains the information from ‘Graph 1’ but in separate graphs.
Graph A: Graph showing the field strength with no vehicle present
Graph B: Graph showing the field strength with a car present
48834
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48838
48840
48842
48844
48846
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48850
48852
05101520
FieldStrength(nT)
Distance (m)
Field Strength (nT)
No Vehicle
48650
48700
48750
48800
48850
48900
05101520
FieldStrength(nT)
Distance (m)
Field Strength (nT)
Car

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Ethan Dodd
Physics
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Graph C: Graph showing the field strength with a 4x4 present
Graph D: Graph showing the field strength with a van present
47800
48000
48200
48400
48600
48800
49000
05101520
FieldStrength(nT)
Distance (m)
Field Strength (nT)
4x4
47200
47400
47600
47800
48000
48200
48400
48600
48800
49000
05101520
FieldStrength(nT)
Distance (m)
Field Strength (nT)
Van

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Physics
25 | P a g e
Graph E: Graph showing the field strength with a small truck present
46500
47000
47500
48000
48500
49000
05101520
FieldStrength(nT)
Distance (m)
Field Strength (nT)
Small Truck

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Ethan Dodd
Physics
26 | P a g e
4.3 Appendix III
Raw Data from Experiment 2
Table A: Data with no steel cube present
Distance
(cm, ± 1cm)
Field Strength (T, ± 5x10-10
T)
1 2 3 4 5
100 0.26891E-4 0.26889E-4 0.26887E-4 0.26893E-4 0.26891E-4
90 0.26887E-4 0.26891E-4 0.26889E-4 0.26886E-4 0.26892E-4
80 0.26889E-4 0.26889E-4 0.26892E-4 0.26885E-4 0.26888E-4
70 0.26893E-4 0.26891E-4 0.26895E-4 0.26886E-4 0.26889E-4
60 0.26886E-4 0.26893E-4 0.26887E-4 0.26886E-4 0.26889E-4
50 0.26892E-4 0.26889E-4 0.26887E-4 0.26892E-4 0.26891E-4
40 0.26872E-4 026885E-4 0.26888E-4 0.26893E-4 0.26887E-4
30 0.26892E-4 0.26887E-4 0.26892E-4 0.26886E-4 0.26893E-4
20 0.26888E-4 0.26893E-4 0.26887E-4 0.26890E-4 0.26886E-4
10 0.26889E-4 0.26890E-4 0.26888E-4 0.26887E-4 0.26903E-4
Table B: Data with 1kg steel cube present
Distance
(cm, ± 1cm)
T)
1 2 3 4 5
100 0.26889E-4 0.26891E-4 0.26887E-4 0.26893E-4 0.26890E-4
90 0.26887E-4 0.26890E-4 0.26889E-4 0.26888E-4 0.26888E-4
80 0.26887E-4 0.26886E-4 0.26887E-4 0.26887E-4 0.26886E-4
70 0.26883E-4 0.26885E-4 0.26882E-4 0.26887E-4 0.26884E-4
60 0.26884E-4 0.26882E-4 0.26879E-4 0.26882E-4 0.26882E-4
50 0.26876E-4 0.26881E-4 0.26879E-4 0.26879E-4 0.26880E-4
40 0.26873E-4 0.26875E-4 0.26872E-4 0.26879E-4 0.26880E-4
30 0.26873E-4 0.26873E-4 0.26869E-4 0.26870E-4 0.26871E-4
20 0.26866E-4 0.26863E-4 0.26865E-4 0.26868E-4 0.26867E-4
10 0.26861E-4 0.26865E-4 0.26864E-4 0.26862E-4 0.26861E-4

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Table C: Data with 2kg steel cube present
Distance
(cm, ± 1cm)
T)
1 2 3 4 5
100 0.26889E-4 0.26893E-4 0.26892E-4 0.26887E-4 0.26891E-4
90 0.26887E-4 0.26887E-4 0.26889E-4 0.26887E-4 0.26887E-4
80 0.26889E-4 0.26888E-4 0.26887E-4 0.26888E-4 0.26887E-4
70 0.26886E-4 0.26886E-4 0.26885E-4 0.26886E-4 0.26884E-4
60 0.26880E-4 0.26879E-4 0.26883E-4 0.26882E-4 0.26882E-4
50 0.26875E-4 0.26875E-4 0.26879E-4 0.26875E-4 0.26876E-4
40 0.26869E-4 0.26870E-4 0.26868E-4 0.26868E-4 0.26869E-4
30 0.26865E-4 0.26866E-4 0.26866E-4 0.26864E-4 0.26866E-4
20 0.26859E-4 0.26859E-4 0.26855E-4 0.26856E-4 0.26857E-4
10 0.26848E-4 0.26849E-4 0.26850E-4 0.26849E-4 0.26850E-4
Table D: Data with 3kg steel cube present
Distance
(cm, ± 1cm)
T)
1 2 3 4 5
100 0.26889E-4 0.26887E-4 0.26887E-4 0.26892E-4 0.26890E-4
90 0.26891E-4 0.26887E-4 0.26889E-4 0.26887E-4 0.26890E-4
80 0.26886E-4 0.26887E-4 0.26888E-4 0.26886E-4 0.26886E-4
70 0.26885E-4 0.26886E-4 0.26885E-4 0.26884E-4 0.26884E-4
60 0.26879E-4 0.26880E-4 0.26879E-4 0.26877E-4 0.26881E-4
50 0.26876E-4 0.26875E-4 0.26876E-4 0.26878E-4 0.26876E-4
40 0.26864E-4 0.26865E-4 0.26869E-4 0.26865E-4 0.26866E-4
30 0.26875E-4 0.26873E-4 0.26871E-4 0.26876E-4 0.26870E-4
20 0.26854E-4 0.26859E-4 0.26854E-4 0.26856E-4 0.26855E-4
10 0.26843E-4 0.26845E-4 0.26844E-4 0.26844E-4 0.26843E-4

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Table E: Data with 4kg steel cube present
Distance
(cm, ± 1cm)
T)
1 2 3 4 5
100 0.26890E-4 0.26889E-4 0.26891E-4 0.26892E-4 0.26888E-4
90 0.26888E-4 0.26887E-4 0.26889E-4 0.26887E-4 0.26886E-4
80 0.26886E-4 0.26885E-4 0.26886E-4 0.26885E-4 0.26886E-4
70 0.26882E-4 0.26883E-4 0.26881E-4 0.26883E-4 0.26886E-4
60 0.26878E-4 0.26878E-4 0.26877E-4 0.26878E-4 0.26879E-4
50 0.26877E-4 0.26877E-4 0.26873E-4 0.26875E-4 0.26874E-4
40 0.26870E-4 0.26867E-4 0.26863E-4 0.26865E-4 0.26865E-4
30 0.26863E-4 0.26862E-4 0.26863E-4 0.26862E-4 0.26862E-4
20 0.26852E-4 0.26853E-4 0.26850E-4 0.26851E-4 0.26853E-4
10 0.26839E-4 0.26842E-4 0.26832E-4 0.26836E-4 0.26834E-4
All of the uncertainties in this section have been derived from the accuracy of the instrument used to
take the measurements and recordings, so a tape measure (+ 1cm) and the magnetic sensor (+ 5x10-
10
T).

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4.4 Appendix IV
This appendix contains the information of ‘Graph 2’ but in separate graphs.
Graph A: Graph showing the field strength with no cube present
Graph B: Graph showing the field strength with a 1kg cube present
26884
26885
26886
26887
26888
26889
26890
26891
26892
05101520
FieldStrength(nT)
Distance (m)
Field Strength (nT)
No Cube
26860
26865
26870
26875
26880
26885
26890
26895
05101520
FieldStrength(nT)
Distance (m)
Field Strength (nT)
1kg Cube

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Graph C: Graph showing the field strength with a 2kg cube present
Graph D: Graph showing the field strength with a 3kg cube present
26845
26850
26855
26860
26865
26870
26875
26880
26885
26890
26895
05101520
FieldStrength(nT)
Distance (m)
Field Strength (nT)
2kg Cube
26840
26845
26850
26855
26860
26865
26870
26875
26880
26885
26890
26895
05101520
FieldStrength(nT)
Distance (m)
Field Strength (nT)
3kg Cube

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Graph E: Graph showing field strength with a 4kg cube present
26830
26840
26850
26860
26870
26880
26890
26900
05101520
FieldStrength(nT)
Distance (m)
Field Strength (nT)
4kg Cube

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5. REFERENCES
5.1 Images Cited
Dunbar, Brian. "2012: Magnetic Pole Reversal Happens All The (Geologic) Time."
NASA. NASA, 05 Dec. 2011. Web. 09 Sept. 2014.
World Magnetic Model. Digital image. National Geophysical Data Center. N.p., Jan.
2010. Web. 16 Sept. 2014.
Wall, Mike. "Sun Unleashes Major Solar Flare at Earth (Video)." Space.com. N.p., 10
Sept. 2014. Web. 22 Sept. 2014.
5.2 Works Cited
Gilbert, William, and Aaron Dowling. De Magnete, Magneticisque Corporibus, Et De
Magno Magnete Tellure. N.p.: Paul Fleury Mottelay, 1893. Print.
Glaztmaier, Gary A., and Paul H. Roberts. "WHEN NORTH GOES SOUTH."
Projects in Scientific Computing (1996): n. pag. Psc.edu. Pittsburgh Supercomputing
Center. Web. 22 July 2014.
Hejda, Pavel, and Josef Bochníček. Geomagnetically Induced Pipe-to-soil Voltages in
the Czech Oil Pipelines during October–November 2003. Tech. Prague: Annales
Geophysicae, 2005. Print.
Jankowski, Jerzy, and Christian Sucksdorff. "GUIDE FOR MAGNETIC
MEASUREMENTS AND OBSERVATORY PRACTICE." (1996): 49-50. Print
Pallardy, Richard. "Dynamo Theory (geophysics)." Encyclopedia Britannica Online.
Encyclopedia Britannica, n.d. Web. 22 July. 2014.
"Rugged Overhauser Magnetometer." Gem Systems. GEM, n.d. Web. 03 Sept. 2014.
Stern, David P., Dr. "Origin of The Earth's Magnetism." The Great Magnet, the Earth.
Lab. for Extraterrestrial Physics, Goddard Space Flight Center (NASA), 23 Feb. 2008.
Web. 28 July 2014.

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