Introduction: (Initial Observation)
There is a great controversy on health effects of electromagnetic fields. Some are using electromagnetic fields as a tool for treatment of pain and certain disease. Others are avoiding it totally and believe that electromagnetic fields cause cancer and other health problems. While many are interested on the health effects of electromagnetic fields on human, I like to see how do electromagnetic fields affect other live organisms such as plants. Plants can emerge from seeds and grow to young plants in a short period of time (about 2 to 3 weeks). So I can test the effects of electromagnetic fields on plants.
I may discover positive effects. For example electromagnetic fields may accelerate seed germination. If that happens, farmers and growers can benefit from that by planting their seeds in an electromagnetic field and then transfer young plants to the farm or to larger pots in a green house. If it has negative effects, then they will know to avoid electromagnetic field while planting seeds.
Adult supervision and consulting with an electrician is required in selecting and setup of electrical components of experiments.
Information Gathering:
Gather information about electromagnetic fields. Look it up in dictionaries and encyclopedias (online or books). Find out how electricity and magnetism can be converted to each other. Learn about the devices that produce electromagnetic fields and the mechanism of such production. Learn about measuring electromagnetic fields and gauss meter. Find out about what is the public opinion on the effects of electromagnetic forces. Keep track of where you got your information from.
Read the material about using electromagnetic field to promote health and treatment of certain disease. To find such reports on the Internet, search for keywords “Electromagnetic Field + Treatment”. Following are some sample information that you may find.
http://www.curatron.com/PEMF-MS-Abstracts.pdf
http://infoventures.com/emf/currlit/bu15144.html
http://users.med.auth.gr/~karanik/english/articles/emf6.html
Also read about health hazards contributed to electromagnetic fields. Many believe that electromagnetic fields can cause cancer and chronic disease. To search for those reports who believe electromagnetic fields cause disease, search the Internet for keywords “Electromagnetic fields cause”. Following are some sample information that you may find.
http://www.relfe.com/electromagnetic.html
http://www.arrl.org/news/rfsafety/hbkrf.pdf
http://www.who.int/peh-emf/about/WhatisEMF/en/index2.html
You may also search for “Electromagnetic + cancer” or “Electromagnetic + disease”.
You can find definitions of magnetic field, electric field and electromagnetic field/ wave in many places, however I would like to offer you my own definitions as well:
Magnetic Field is the region around a magnet or an electric current, characterized by the existence of a detectable magnetic force at every point in the region and by the existence of magnetic poles. You may use a compass to detect magnetic field. Earth is like a large magnet and we are living in a magnetic field every day of our lives. I have not seen any claim that magnetic field may be harmful to people and other live organisms, however there are many claims that strong magnetic field has therapeutic effects and can relief pain and cure cancer. A regular electromagnet connected to a battery, produces the same type magnetic field as a regular magnet. Any direct electric current in a conductor such as a wire does create a small magnetic field around the wire.
Electric Field is a region of space characterized by the existence of a force generated by electric charge. Electric field in clouds is the cause of lightening. High voltage power lines are not insulated because surrounding electric field is so big that it simply exceeds any thick rubber or plastic insulator. A person standing on the ground can be electrocuted by taking his hand close to a high voltage power cable. No physical contact is required. Electric field around a high voltage cable is enough to initiate an electric arc between the hand and the cable.
Electromagnetic Field (I like to call it a moving magnetic field) is a field of force associated with electric charge in motion, having both electric and magnetic components and containing a definite amount of electromagnetic energy. A better name for that is Electromagnetic wave. A moving magnet can create an electromagnetic field. An electromagnetic field can induce electric force on any conductor (wire) passing through the field. That is the way that electric generators are made. The reason that a moving magnet can induce electricity is that magnets can force electrons out of their path, so moving magnet can move electrons and movement of electrons is electricity.
A good experiment to see how magnets can bend an electron beam, is taking a magnet close to the TV screen or computer monitor. (This test may cause a permanent discoloration on TV or monitor. Be careful in doing that. Do this test with an old monitor or TV and try the center area of the screen for lower risk of permanent discoloration).
With so many radio stations and TV stations and cellular phones and AC electric equipment, we are always surrounded by a weak electromagnetic field. I have not test it myself, but I think in many areas you may get some free electricity from electromagnetic fields in the air. So in this project we are not talking about weak electromagnetic fields, instead we focus on a strong electromagnetic field.
Finally electromagnetic waves have different frequencies (different wave lengths).
Light, microwaves, x-rays, and TV and radio transmissions are all kinds of electromagnetic waves. They are all the same kind of wavy disturbance that repeats itself over a distance called the wavelength. (See demo). We already know that light is good for plants. Here we focus on low frequency (50 Hertz) electromagnetic waves produced by electric equipment and electric wires found around the house.
If you want to modify this project and test the effects of a strong magnetic field on plant growth, you can simply substitute any source of electromagnetic wave with regular ceramic or metalic magnets.
Project Advisor
Question/ Purpose:
What do you want to find out? Write a statement that describes what you want to do. Use your observations and questions to write the statement.
The purpose of this project is to see how electromagnetic fields (EMF) may affect seed germination and plant growth.
The abbreviation EMF stands for electromagnetic fields. They are produced when electricity flows through a wire. The fields are silent and invisible. Humans are not biologically equipped to detect them. They go unnoticed even though we’re surrounded by EMF’s all the time. You can be exposed to EMF’s anywhere electricity flows such as through power lines, microwave ovens, electric ranges, electric razors, hair dryers, television sets, computers, air conditioners, and electric clocks.
Identify Variables:
When you think you know what variables may be involved, think about ways to change one at a time. If you change more than one at a time, you will not know what variable is causing your observation. Sometimes variables are linked and work together to cause something. At first, try to choose variables that you think act independently of each other.
Independent (manipulated) variable in my experiment is the presence or absence of a strong electromagnetic field.
Dependent (responding) variables are the rate of seed germination, the growth of the plants (plants height) , the number of leaves on each plant, the color of the leaves, and the health of the plants.
Controlled variables are light, temperature, air, soil type, seed type, pot size, seed depth and all other environmental conditions of experiment.
Hypothesis:
Based on your gathered information, make an educated guess about what types of things affect the system you are working with. Identifying variables is necessary before you can make a hypothesis. This is a sample hypothesis:
My hypothesis states that electromagnetic fields will have a positive effect on seed germination and plant growth. My hypothesis is based on my gathered information that light also is an electromagnetic wave. Since light is good for plants, other electromagnetic waves may be good as well.
Experiment Design:
Design an experiment to test each hypothesis. Make a step-by-step list of what you will do to answer each question. This list is called an experimental procedure. For an experiment to give answers you can trust, it must have a “control.” A control is an additional experimental trial or run. It is a separate experiment, done exactly like the others. The only difference is that no experimental variables are changed. A control is a neutral “reference point” for comparison that allows you to see what changing a variable does by comparing it to not changing anything. Dependable controls are sometimes very hard to develop. They can be the hardest part of a project. Without a control you cannot be sure that changing the variable causes your observations. A series of experiments that includes a control is called a “controlled experiment.”
Experiment 1:
Introduction: In this experiment you experiment growing radish seeds in an electromagnetic field caused by a coil of wire connected to AC electric current. Be aware that making and operating any device that may cause interference in communication devices such as radio and TV is against the law and FCC (Federal Communication Commission) is enforcing this low.
Material:
- 120 rapid radish seeds for two experiment trials
- 2 identical pots
- Potting soil
- Electromagnetic generator (See the list of material below)
Optional: Gauss meter capable of EMF and ELF (Extreme-Low Frequency) detection.
You may also want to make your own Gauss meter.
Procedure:
- Get two pots and plant 30 radish seeds in each pot. Plant the seeds in a depth of one centimeter in potting soil.
- Place both pots in front of a large, sunny picture window. Both pots must receive the same amount of sunlight and water each day. Place the pots at least one meter apart.
- Label one pot as control and the other pot as electromagnetic field.
- Place an electromagnetic wave generator next to the experimental pot labeled electromagnetic.
- If you have a gauss meter, measure the electromagnetic field around each pot.
- Water the plants every day. Make daily observations and record your data in a data sheet. Your data must include date, number of germinated seeds, average height of plants, average number of leaves per plant, color of plants and general health of plants.
- Record your findings for 14 days in each of your trials. You may make 2 or more trial experiments and analyze the resulting data to draw a conclusion.
So, what is an electromagnetic wave generator?
Any transformer or coil of wire attached to an DC electricity can be used as an electromagnetic wave generator. The transformer that you use must give AC output. AC stands for Alternative Current.
A good electromagnetic generator can be made by connecting a coil of insulated wire (about 200 loop, 1″ diameter) to a 24 volts AC output of an AC transformer. For best results, wrap the insulated wire around an Iron core. Iron core can be a small dumbbell, iron rod or a bunch of long nails wrapped together in a bunch by masking tape.
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| There are two coils and one core in each transformer. |
This is a picture of an AC transformer. |
The transformer that you use, does not need to be a plug-in transformer like the one shown above. In this way you can place both the transformer and the coil close to the experiment pot. If you have a plug-in transformer, you need to use an extension cord to bring both the transformer and coil next to the plant. If you can not find a 24 volts AC transformer, use a 16 volt transformer.
If you don’t have supervision and support of someone familiar with electrical circuits, skip the electromagnetic wave generator and replace it with a long electric cord connected to a light bulb. Make a coil of the long electric cord and use that as a source of electromagnetic waves. The light bulb must be on, otherwise there will be no electric current in the wire.
Not enough light?
If for any reason you don’t have access to enough light for your plants, use fluorescent lights for plants. A special type of fluorescent light known as grow light, provides the best light for plant growth. Hang fluorescent lights about 1 foot above the plants.
Experiment 2:
High Voltage Simulated Power Line Construction
Introduction: This experiment is very similar to the previous experiment. The only difference is that you use higher voltage and use a different design of electromagnetic field generator.
Design a safe plan for the construction of the electromagnet, which simulates the power lines.
Material:
- Two Iron rods about 1 foot each and diameter of 1/2″ up to 2″
- 100 feet insulated, single strand copper wire gauge 24 for the coil
- Additional insulated wire gauge 18 for the distance from plug to the light bulb and from the light bulb to the coil.
- one 90 watt or 100 watt light bulb
- Screw base for the light bulb
- PVC tape or other insulating tapes to properly insulate electrical connections.
- PVC tape or masking tape to secure the coil and prevent unwinding.
Procedure:
- Make sure the work area is clean and uncluttered
- Check with people who have experience with electricity before proceeding
- Inform teachers and supervisors of your actions
- Obtain all necessary materials for the construction
- Put the two iron rods so they are parallel and the same length together. Bind them with tape on both ends and in the middle
- Leave about 20 cm of wire then wrap the rest (30meters or 100 feet) around the two iron rods tightly. Be sure to tape the coil down in case a mistake is made
- Bring the end of the wire, (which was left over from wrapping) back to the opposite end with the 20cm you started with
- Make sure the light bulb holder is unplugged
- Carefully connect the 2 ends from the iron rod to the light bulb holder to make a complete circuit. Use caution because electricity will pass through this.
- Place a incandescent 90W light bulb in the holder
- Plug the cord from the light bulb holder in and be sure the light bulb works. There should be no heat generated by the coil
- Test that the coil produces EMF by holding screw driver at one end of the metal bar. Metal bar is supposed to be magnetized and may vibrate the screw driver. You can now unplug the light.
- Suspend the iron rods approximately 10cm above the experiment pot.
- Power the electromagnet by plugging it in.
The above figure shows a simplified schematic of connecting coil, light bulb and the plug. You will need to use insulated wires and approved electrical material. You must also wrap another layer of PVC tape or masking tape over the coil to keep it secure. Consult an electrician about the safety of your setup. Note that the coil and the light bulb are connected in a series. The purpose of light bulb here to restrict the electric current to a safe level.
All the steps of experiment will be the same as experiment 1.
Materials and Equipment:
List of material can be extracted from each experiment details.
Results of Experiment (Observation):
Experiments are often done in series. A series of experiments can be done by changing one variable a different amount each time. A series of experiments is made up of separate experimental “runs.” During each run you make a measurement of how much the variable affected the system under study. For each run, a different amount of change in the variable is used. This produces a different amount of response in the system. You measure this response, or record data, in a table for this purpose. This is considered “raw data” since it has not been processed or interpreted yet. When raw data gets processed mathematically, for example, it becomes results. Following is a sample results. We have not verified the accuracy of the information.
In trial one, all seeds had germinated in the experimental and control pots after four days. On the fourth day, both the control and experimental group of plants grew an average of one and a half centimeters tall. On the fifth day, both groups of plants grew to an average two and a half centimeters tall. On the sixth day, the control plants were an average four centimeters tall and the experimental plants were three and a half centimeters tall. On the seventh day, the control plants were six and a half centimeters tall and the experimental plants were six centimeters tall. On the eighth day, the control plants were seven centimeters tall and the experimental plants were six and a half centimeters tall. On the ninth day, the control plants were an average of eight centimeters tall and the experimental plants were an average of seven and a half centimeters tall. On the tenth day of the experiment, the control plants were eight and a half centimeters tall and the experimental plants were eight centimeters tall. The plants stopped growing on the eleventh day. All plants in the control and experimental pots had two leaves by the end of the ninth day of the experiment. All plants had two leaves by the end of the 14th day of the experiment. The color of all plants in the control and experimental pots was green and their health was good. In trial two, all seeds had germinated in the experimental and control pots after four days. On the fourth day, the control plants grew to an average of two centimeters tall and experimental group of plants grew an average of three centimeters tall. On the fifth day, the control plants grew to an average three centimeters tall and the experimental plants grew to an average of four centimeters tall. On the sixth day, the control plants were an average five centimeters tall and the experimental plants were six centimeters tall. On the seventh day, the control plants were six centimeters tall and the experimental plants were six and a half centimeters tall. On the eighth day, the control plants were seven centimeters tall and the experimental plants were six and a half centimeters tall. On the ninth day, the control plants were an average of seven centimeters tall and the experimental plants were an average of seven and a half centimeters tall. On the tenth day of the experiment, the control plants were seven centimeters tall and the experimental plants were eight centimeters tall. The plants in both pots stopped growing on the tenth day. All plants in the control and experimental pots had two leaves by the end of the ninth day of the experiment. All plants had two leaves by the end of the 14th day of the experiment. All plants were green and were in good health through out the second trial.
Calculations:
The only calculation that you may need to do is taking the average of plant height in your daily observations.
Summary of Results:
Summarize what happened. This can be in the form of a table of processed numerical data, or graphs. It could also be a written statement of what occurred during experiments.
It is from calculations using recorded data that tables and graphs are made. Studying tables and graphs, we can see trends that tell us how different variables cause our observations. Based on these trends, we can draw conclusions about the system under study. These conclusions help us confirm or deny our original hypothesis. Often, mathematical equations can be made from graphs. These equations allow us to predict how a change will affect the system without the need to do additional experiments. Advanced levels of experimental science rely heavily on graphical and mathematical analysis of data. At this level, science becomes even more interesting and powerful.
The only difference between the two trials was that in the first trial the control plants which did not receive the strong electromagnetic field grew to an average height of nine centimeters while the experimental plants growing in the strong electromagnetic filed grew to an average height of eight centimeters. In the second trial, the control plants grew to an average of seven centimeters and the experimental plants grew to an average of eight centimeters. I averaged my data for both trials. The control and experimental plants both grew to an average height of eight centimeters tall. The plants in the control and experimental pots all germinated at about the same time in the first and second trial. All the plants had two leaves, were green in color, and in good health by the end of the experiment.
Conclusion:
Using the trends in your experimental data and your experimental observations, try to answer your original questions. Is your hypothesis correct? Now is the time to pull together what happened, and assess the experiments you did. Following is a sample conclusion. We have not verified the accuracy of the data. You need to do your own experiments.
I reject my hypothesis which stated that electromagnetic fields will have an effect on plant growth. On average, there was no difference between the growth in the control and experimental plants. So EMF’s do not seem to effect plant growth. The findings in this research should not be generalized to animal and human growth or health. Therefore, while EMF’s may not affect plants growing in a garden, they still may affect the gardener.
Related Questions & Answers:
What you have learned may allow you to answer other questions. Many questions are related. Several new questions may have occurred to you while doing experiments. You may now be able to understand or verify things that you discovered when gathering information for the project. Questions lead to more questions, which lead to additional hypothesis that need to be tested.
Possible Errors:
If you did not observe anything different than what happened with your control, the variable you changed may not affect the system you are investigating. If you did not observe a consistent, reproducible trend in your series of experimental runs there may be experimental errors affecting your results. The first thing to check is how you are making your measurements. Is the measurement method questionable or unreliable? Maybe you are reading a scale incorrectly, or maybe the measuring instrument is working erratically.
If you determine that experimental errors are influencing your results, carefully rethink the design of your experiments. Review each step of the procedure to find sources of potential errors. If possible, have a scientist review the procedure with you. Sometimes the designer of an experiment can miss the obvious.
