"ELECTROMAGNETIC SPECTRUM ON TRIAL"

©1995 The Regents of the University of California

Description

One tool you can use for the trial is the electronic evidence forum.

The "trial" of a physical phenomenon is an interesting form of a lesson. We can thus "try" friction and electrical resistance, inertia and resonance, classical physics, etc. Such lessons are principally aimed at consolidating and systematizing students' knowledge, and at showing that there is a connection between science and real life.

The idea of organizing educational games such as trials on physical phenomena was first introduced by Irina Lanina, Professor of Education at St. Petersburg Pedagogical University, Russia. (I. Lanina, "Not by a lesson alone (Ne urokom edinym)," Moscow, Prosvescheniye, 1991.)Note: The trial format can be used to teach many different subjects including topics from history, art, mathematics, etc.

As part of this activity, students will put the different types of the electromagnetic radiation "on trial", selecting the judge, prosecutor, defense counsel, and jury, and learning about electromagnetic energy by arguing the pros and cons of each wavelength. The "Trial" is a format which allows students to explore electromagnetic radiation properties. The different types of electromagnetic radiation will serve as the "defendants" who are accused of properties which may or may not be true for that particular wavelength.

The educational game is organized as follows:

1. Students are divided into two main groups: defense witnesses and prosecution witnesses. Their homework (started at least a week prior to the "trial") is to find the benefits and negative effects of a particular type of radiation.

2. The judge, the prosecutor, the counselor for the defense, the defendant (electromagnetic spectrum), and the jury are selected from among the students of a class.

3. The rules of the game and the duties of each trial participant should be explained in detail some time before the lesson.

4. To make the trial more interesting, the speeches of the witnesses are to be accompanied by experiments and visual aid presentations.

5. The real "biography" of the accused spectrum can be made into the public appearance of the "defendant", and the jury should ask questions to specify the details and to try to make the whole process of the trial more effective and animated.

6. At the end of the lesson the teacher should explain his/her attitude toward the whole process of the "Trial" and stress the most interesting details. A discussion of merits and shortcomings of the lesson can be also conducted during the next period.

Here is an example of such a trial:

Participants:

1. Chief Judge (C. J.)
2. Electromagnetic spectrum (six defendants) (E. S.)
3. Chief Prosecutor (C. P.)
4. Counselor for the Defense (C. D.)
5. Witnesses for the Prosecution (W. P.)
6. Witnesses for the Defense (W. D.)
7. Secretary of the trial (S.)
8. Jury (J.)

Minutes of the Trial:

• C. J.: Today we will consider Case # 1235. Electromagnetic waves are accused of different kinds of damage. I appeal to the Honorable Jury for the impartial examination of this case in order to arrive at a just sentence.

• S.: Bring in the accused Family of Electromagnetic Waves.

• C. J.: Let us determine the personalities of the accused. Tell us your names, please.

• E. S.: We are a Family of Electromagnetic waves. There are six of us in our spectrum: Radio waves, Infrared waves, Light waves, Ultraviolet waves, X-rays, and Gamma rays.

• C. J.: Who are your parents?

• E. S.: James Maxwell and Heinrich Hertz can be considered our parents. In 1980s, J. Maxwell introduced us to a scientific world by creating a special theory of electromagnetism. In 1887 (unfortunately, 8 years after Maxwell's death), H. Hertz experimentally generated and detected waves using a spark-gap apparatus. He even measured our speed, which turned out to be exactly the speed of light, just as Maxwell had predicted in his theory!

• C. J.: Can you explain to us more clearly who you are. Give us the definition of the electromagnetic spectrum, if you will.

• E. S.: Electromagnetic spectrum form a "family" that includes all types of electromagnetic waves existing in the Universe.

• C. J.: Who has questions to the accused spectrum. The Honorable Counsel for the Prosecution.

• C. P.: No questions so far, your Honor.

• C. J.: Counselor for the Defense?

• C. D.: I have a question. Will the Jury take into account the fact that the parents of Electromagnetism were such famous and outstanding scientists.

• C. J.: The Jury will examine all facts.

• C. D.: Then I have no more questions at this point.

• C. J.: Questions to the accused family, please.

• J.: Where can electromagnetic waves appear?

• E. S.: You can meet us at home, you can find us outdoors, we can exist even in empty space! Engineers and workers, scientists and medical personnel use us for different purposes.

• C. J.: Before hearing this strange case, I would like to show you some telegrams, videos, and faxes.

• S.: A telegram from a group of scientists: W. Hershel, W. Roentgen, A.Beckerel.

  "We, the physicists who discovered three types of invisible electromagnetic radiation (Infrared, X-rays, and Gamma Rays), want to make a statement. Electromagnetic waves, both visible and invisible, are very important sources of information for people. When we discovered them (sometimes accidentally), we did not know what their properties were or how to use hem. We hope you will not be too harsh with our inventions." (The telegram is accompanied by a description of the experiments conducted be Hershel, Roentgen, and Beckerel.)

• S.: A video from H. Hertz.

  "I would like to remind you that only a curious and hardworking researcher can achieve success. In 1878 I proved that electromagnetic waves did indeed exist. Numerous discoveries have been made since then, and I am sure that many clever technical devices using different types of electromagnetic waves will be created in the future. This is why I would like to tell you, my young friends, that if you look closely at this wonderful family of waves you will see that their existence is a miracle and a blessing to the mankind." (The speech is accompanied by a description of the Hertz's experiment.)

• S.: A fax from J. Maxwell.

  "My name is J. Maxwell. I am a physicist and a mathematician. At the end of the 19th century I solved an interesting problem. Based on experimental data obtained by Faraday, Oersted, and other scientists, I combined electric and magnetic phenomena in my famous equations. That is why I am usually called " the stepfather of electromagnetism." I am very proud of this fact. My theory is magnificent, but it cannot exist without pure scientific experiments. I hope you will use all your knowledge and tolerance, and will acknowledge the contribution my children made to the development of electromagnetism." (Main formulas of the Maxwell's theory of electromagnetism are demonstrated before the audience.)

• C. J.: I think it is time to begin the trial. Please call witnesses for the prosecution.

  W. P. # 1, Mr. Smith:

  " I am a professional cook. All my life I've been using conventional stoves to prepare food. Recently the manager of our restaurant bought new microwaves ovens. This changed everything. Some members of our staff began feeling sick. I decided to make a research on microwaves. Now I know that they are members of an entire family of waves. They are considered to be the shortest radio waves. Their property is that they are absorbed by liquids. That is why we can use them to prepare food. On the other hand, we are human beings, and our bodies contain water just like the bodies of other living organisms. The result is that our bodies also absorb microwaves! I think that it is dangerous to use them very often in our everyday life, and we should put a stop to such use without further delay"

• W. P. # 2:

  "My name is Lee. I am 15 years old, and I like listening to modern music and watching TV. I spend all my money buying stereo systems, VCR's, CD players, and stuff. It means that I use various types of radio waves: long, short, FM, AM, and microwaves. I am confused about their properties and do not know which of them to use and when. They say that different types of radio waves undergo reflection, diffraction, and other transformations when they travel in space. What also irritates me is that all the equipment I use is so unreliable. There is always static and interference, signals are clear one moment and fade away the next. Radio waves are supposed to help people communicate, but sometimes I think they are bothersome rather than helpful."

• W. P. # 3:

  "My name is Fox, and I travel a lot. I like to climb mountains, to cross deserts, to take part in sea voyages. But the problem is that every time I travel I develop skin problems. No matter what I do, my skin is always red and dry. It is only recently that I understood the reason. All my problems are related to ultraviolet radiation! Our Sun is a powerful source of UV, and although the atmosphere absorbs most of the ultraviolet, the radiation still hurts people, causing not just redness of skin, but also other serious problems, such as skin cancer. It is disgusting! Something should be done about this radiation."

• W. P. # 4, Ms. Lakisha Thompson:

  " I am an amateur astronomer. I was always interested in ultraviolet radiation. I even invented a special UV detector to help me in my work. But because UV waves are readily absorbed by the Earth's atmosphere, I am unable to continue my research. I don't know how to make my detectors work. I probably should not have developed these detectors in the first place. I think ultraviolet radiation is useless as a scientific tool."

  W. P. # 5, Mr. Smog:

  " I am a professional physician with considerable experience. I treated many patients for a variety of diseases. I noticed that the number of children suffering from leukemia and other types of cancer has sharply risen in the last 15 years. My colleagues tried to find the cause of this disease. We investigated hundreds of affected children in order to obtain the necessary data. We concluded that there is a direct relation between some types of electromagnetic waves (especially X-rays and gamma rays) and the incidence of these dangerous diseases. I do not know what happened to our atmosphere and its ozone layer, but more and more waves can go through it now. These waves damage and destroy living tissue, alter metabolism in humans, and even cause mutations in living cells. That is why I accuse the family of electromagnetic spectrum! We should give this phenomena a real fight! I demand it on behalf of my poor little patients. We must relieve their suffering."

• C. J.: I think that the prosecution was given enough opportunity to present their case. We now invite the witnesses for the defense.

• W. D. # 1:

  " My name is Tom Gardini. I am the owner of a unique automobile which is called the electric car. I am so proud of my car! First of all, I don't need to pay for gas. But the main advantage of this car is that it does not pollute the environment, because my car has no internal combustion engine or diesel engine. Its heart is an electric motor, and its lungs are solar panels that convert the energy of light into electric energy. This is why I want to thank electromagnetic waves, which help people in their search for alternative sources of energy. I am using solar batteries for different purpose at home: to heat water in my pool, to operate the air conditioner, and even to illuminate my garden."

• W. D. # 2, Ms. Nghuen:

  "I have been working as a professional photographer for ten years now. Every day I marvel at how light can make the film in my camera produce beautiful images of objects. But now I am even more fascinated by the properties of invisible infrared waves. Isn't it wonderful that heat waves allow you to produce pictures of different objects. Using special cameras, you can form images that are otherwise invisible. We must be grateful to Mr. Hershel for his ability to investigate the unknown. Now we can use IR not only for military purposes, but also in astronomy. For example, we can get information about large low-temperature astronomical objects such as Betelgeuse in the Orion constellation; this star is considered to be a powerful source of IR waves. I can tell you that I am more than happy to use infrared photography in my work."

• W. D. # 3:

  " I am an avid reader. Most of all I like to read technical magazines and scientific articles. The most intriguing thing for me is that many modern inventions and discoveries are based on electromagnetic waves and their properties. Only recently I found many examples of this phenomenon, such as electromagnetic pumps, electromagnetic space engines, electromagnetic medicine, and electromagnetic universe. To tell you the truth, I don't understand how you can accuse waves that play such an important role in our lives. Don't you realize that we still inhabit this planet only because of electromagnetic radiation?

• W. D. # 4, Ms. Dawkins:

  "I am a scientist at the astrophysics laboratory at Berkeley. I am so angry! I definitely have to say something here. I need to defend UV! Our lab is well known to the whole world because of the respectful UV radiation. Right now we are participating in a NASA mission. The main goal of this mission is to analyze extreme UV radiation using a special satellite. Information received as a result of a full-sky survey (lasting 6 months) and a deep survey (along the sun ecliptic) will be studied very carefully, and many discoveries (about white dwarfs, for example) will probably be maid in the future. What I wanted to emphasize is that instead of accusing UV and other types of radiation , we should thank them for what they do for us. Ultraviolet and other waves are ubiquitous, and they are a vital tool in our scientific quest".

• W. D. # 5:

  "My name is Ann. I want to add something. I am a housewife and I have never worked anywhere outside my house. I have four kids and I don't know what I would do without this wonderful family of waves! To tell you the truth, I am using all of them. My kids and I are watching educational programs on TV and listen to the music on the radio. It means that we are using different radio waves - long and short. Sometimes when my kids are sick or hurt, doctors recommend using X-rays to make the right diagnosis, and infrared waves for physical therapy. UV waves help my children to be healthy because small exposure to this radiation stimulates the production of vitamin D in their bodies. It is so wonderful to have the whole family of electromagnetic friends at home."

• W. D. # 6, Mr. Manual Garcia:

  "Good afternoon. I want to apologize for taking your time, but I would like to complement one more type of radiation that is considered to be a very dangerous one. I am responsible for the maintenance of the Gamma Ray observatory, and can assure you that celestial gamma rays allow us to do miracles - to observe the death of a star, to understand the nature of mysterious quasars, pulsars, and even black holes! I urge you to reconsider your negative opinion about electromagnetic waves.

• C. J.: I think we should give the floor to the Chief Prosecutor.

• C. P.:

  Honorable jurors, ladies and gentlemen. We have gathered today in this hall to consider the crimes committed by the electromagnetic gang. We have heard the testimony of only few witnesses for the prosecution, but we already know that all types of waves produce a lot of damage. But the most dangerous thing is the effect on the health of our people, and children in particular. How long shall we continue to be tolerant and patient. It is our duty to prevent this electromagnetic curse from spreading. We should say a resounding "no" to this phenomenon.

• C. J.: The floor is now given to the Counselor for the Defense.

• C. D.:

  The most honorable Chief Judge, members of the Jury. When the electromagnetic spectrum is considered from the legal point of view, it becomes obvious that the phenomenon has more merits then shortcomings. I don't want to repeat what the defense witnesses have told the Jury and the audience when they tried to demonstrate the benefits of electromagnetism. More than that, I want to question the validity of the testimony given by some of the prosecution witnesses. First of all, I want to point out that some of their conclusions about the relation between electromagnetic waves and cancer are still hypotheses, and they are not yet proven. Besides, we can always take measures to prevent their harmful effects. The most important thing is that we need electromagnetic waves, and we need all of them! They are our "brothers and sisters", and we should treat and use them with real respect. I hope that this wonderful family-spectrum will be proven innocent, and quite soon! More than that, our objective today is also to reward Electromagnetic waves for being so helpful to us in our everyday lives.

• C. J.: Having heard both sides, and upon conducting proper deliberations, the Jury delivers the following verdict:

  "After taking into account all useful manifestations of Electromagnetic Waves, on the one hand, and some negligibly negative side effects, on the other hand, the Jury has decided:

  (1) To further employ useful electromagnetic properties by creating new household and industrial devices;

  (2) To continue work directed at reducing damaging side effects of some electromagnetic waves;

  (3) To investigate the validity of the statements that some waves cause different types of cancer;

  (4) To continue using electromagnetic information in trial astrophysics in order to obtain the truthful picture of the Universe for the benefit of the humankind."

• S.: This session is thereby concluded.

At the end of the lesson the teacher explains his/her attitude toward the whole process of the "Trial" and points out the most interesting details. The merits and demerits of the lesson can be discussed during the next period.