“Why is the U.S. government is trying in an era in which they seemingly desperate attempts to reduce health care costs to ban anything that could help people quit smoking?
Smoking is perhaps the most devastating health problem in the United States.

FDA warns of electric cigarette

The federal agency to monitor food and Drug Administration (FDA) held a press conference late last month to warn the Americans against the so-called “e-cigarette”. It was claimed that the electronic cigarette is full of harmful toxins “and” carcinogens. ” Between the lines, the Agency communicated: “Keep this new-fangled, unproven cigarette substitute far better and stay in real cigarettes that are clearly familiar to us all and which are responsible in the U.S. for a year more than 450,000 deaths alone.”

No scientific basis

In which they gave this wrong, incomplete and misleading statement, the FDA violated its long-held tradition, guidelines and recommendations made on the basis solely of scientific knowledge. And while the FDA does, it puts the lives and health of millions of Americans at risk.

The part of the FDA declaration that corresponds to the truth is the fact that e-cigarettes have not yet completed the formal response and security tests of the FDA and that they are only a few years on the market.

What the FDA in the press conference was not known – but would have to be known, is the following:

Smoke kills, not nicotine

Traditional cigarettes are not in the tobacco because of their relatively small quantities present specific “carcinogens” and “toxins” deadly, but because smokers inhale huge amounts of smoke, combustion products. It is the inhaled smoke kills, because cancer in various forms, as well as cardiovascular diseases, lung diseases and many other triggers.

The cigarette was widespread until the invention of mechanical production little. Only after the invention of cigarette-rolling machine, just before the First World War, sales have increased. Previously, tobacco was used relatively “safe”. When the consumption of chewing tobacco, pipes and cigars is inhaled is little or no smoke. Electronic Cigarettes changed all this.

E-cigarette smoker needs to be satisfied

The e-cigarette – a cigarette-like device that is composed of a battery, an atomizer and a cartridge – allows smokers to inhale to get their daily dose of nicotine and clouds to blow into the air (with little or no smell) to imitate the ritual and the sense to smoke regular cigarettes.

The FDA complained that the Electronic Cigarettes is a “nicotine-delivery system. Yes – Nicotine is highly addictive, and it is the nicotine that the smoker “keeps on the hook”. But the supply of nicotine without smoke is a huge health benefit for cigarette smoking (nicotine repositories of e-cigarettes are available in different strengths, and if the user wants it, it may reduce the Nicotine).

Other nicotine delivery systems approved

The FDA has approved other nicotine delivery systems in the form of chewing gum and patches. These systems were all failures unfathomable. The success rate with these tools to a Non smoking to be located, after a year under 15 percent. Millions of dependent smokers are thus condemned to a slow death. We urgently need other alternatives. But the FDA has now joined a long list of so-called health organizations – including the campaign for Tobacco-Free Kids “and” American Lung Association “-. Their motto seems to be common “stop or die.” Not only are these groups reject e-cigarettes, they also condemn other smokeless products such as sinus. Products that have a fraction of the cigarette smoking-related health hazards are bad for health.

Unilateral data collection

A product that provides almost all the “amenities” real smoking, one holds a cigarette in his hand, takes a train and a cloud can ‘smoke’ shows. The FDA lacks evidence that e-cigarettes represent a health risk. It is already so desperate that it openly invites consumers to describe the adverse effects of e-cigarettes. The action aims at preparing a ban on electric cigarettes. Nevertheless, the FDA failed, users of e-cigarettes, who gave up smoking with the help of the call, to describe their positive experiences.

Cigarette smoking remains the leading cause of preventable illness and deaths in the United States. Any acceptable alternative for dependent smokers should be taken seriously. Instead of condemning the Electronic Cigarettes premature, the FDA should encourage studies dealing with the safety and effect of electric cigarettes. Until this is done, should e-cigarettes remain on the market?

Kynar is special material that is made from polyvinylidene fluoride (PVDF). It is a pure and highly non-reactive thermoplastic fluoropolymer. It is used for many different purposes, primarily service applications in wire installation, jacketing, and chemical handling. It has amazing cut-through properties and abrasion resistance, which is combined with high dielectric strength. This dense, high-purity plastic is incredibly resistant to the vast majority of industrial chemicals, fuels, and solvents.

Some of the more notable features of Kynar are: resistance to high temperatures (up to 300° F), amazing resistance to abrasion, non-burning, good mechanical strength, excellent resistance to chemicals, transparency, impressive dielectric strength, semi-rigid, and has outstanding UV resistance. Due to its remarkable properties, this special plastic is utilized in the manufacturing of many products.

Furthermore, Kynar resin has also be used to create other fire-resistant fluoropolymer sheet materials, such as Symalit polyvinylidene fluoride. It is one of the materials that is often used in the building of semiconductor equipment, where protecting against production interruption and property damage is vital. It meets Factory Mutual (FM) 4910 Fire Safe Protocol, and offers noteworthy reduction in the risk of fire, and practically eliminates expensive suppression systems.

In addition, Symalit PVDF 1000 was the first thermoplastic product to meet the strict ASTM E-84 test for non-combustibility, and it is recognized as versatile engineering material, particularly ideal for the manufacture of components for industries, such as nuclear, chemical, petrochemical, pharmaceutical, metallurgical, paper, food, and textile.

It took more than 500 scientists and seven years of research, but the first global earthquake hazard map is now complete. How come it took seven whole years? Well, for starters, the scientists had to contend with forces much greater than earthquakes. Try politics.

The above image shows the pattern of major fault lines throughout the Americas.

Unveiled in San Francisco at the American Geophysical Union, the map shows that about 15 per cent of the Earth’s land is in zones of high or very high hazard – which the researchers define as a 10 per cent chance or greater of violent shaking over the next 50 years. Less than half of the planet’s land is considered a low hazard. But coming up with the numbers once the data were in was the easy part, explains the co-ordinator of the international effort, Domenico Giardini of the Swiss Seismological Service in Zurich.

“The standards by which hazard is done is completely different from country to country. It depends on when it was done, what philosophy they adopted, the quality of data that was available. It was this lack of standards that until now has stalled any effort to look at the global seismic risk in a homogenous way,” says Giardini.

Giardini recalls particular problems. “There were political boundary problems. For example in the Near East, the difficulty of having Syria, Israel and then Jordan and Egypt working together was very difficult,” says Giardini, who also remembers that India and China had never worked together, nor had Turkey, Iran and the former Soviet Union. He recalls the difficulty that grew from the international set of criteria that had to be used – which meant scientists from some countries, in order to comply with the new global standard, had to recalculate their seismological data. “It was very difficult originally, this is why the project lasted so long,” he says, adding that once a consensus was reached and once the scientists got used to working together, “things started to fly.”

Researchers were surprised to learn how high the hazard of earthquakes is throughout the African Rift.

Much as you would expect, the map – which specifically predicts the probability of peak ground acceleration, or an earthquake that most likely damages low-rise buildings – highlights some infamous ground-shaking hotspots, such as southern California, Hawaii and Turkey. But, since for some countries this was the first-ever seismological hazard assessment, the map highlights some new earthquake zones. In Africa, for example – for which there was little data – the hazard is much higher than researchers would have thought. And finding that data was a little harder than they might of thought as well.

In the eastern part of Africa, along the African Rift, much of the historic seismic activity had occurred in unpopulated and undeveloped places. Giardini explains that the hazards we are familiar with are a measure of our memory. Unlike in heavily populated cities, though, memory is short in these kinds of barren regions. In the end, researchers had to go as far away as England to find historic data on past earthquakes in the African Rift. Similarly, some researchers even looked in the Bible to find out the history of earthquakes in the Middle East.

With the new map, which was launched by the International Lithosphere Program with support from the United Nations’ International Decade for Natural Disasters, every country now has information on its own hazardous zones. According to Giardini, the map will be useful for engineers, urban planners and insurers to help regulate codes of design and construction. What the map does not measure, however, is risk from earthquakes.

Seismologists make a distinction between hazard, which is the probability of ground shaking, and risk, which is the probability of damage or of casualties – a multiplication of the hazard by the vulnerability of the building. So Giardini cautions that just because you may live in a high hazard region is no reason to start packing your bags – after all, he says, there are very few completely safe places to live. Instead, cities can limit the impact of an earthquake.

“Now a society can live with earthquakes as it can live with volcanoes, but it has to be prepared for that. So in itself, the hazard can be high, but not necessarily the risk. If you live in a well-built house and your infrastructure is up to standards, then you can live with earthquakes,” says Giardini, who adds, that the difficult part is getting the entire world to achieve this.

Science presumes, through careful, systematic study, that things and events in the universe occur in consistent, comprehensible patterns. Scientists believe that through the use of the intellect, and with the aid of instruments that extend the sens es, people can discover patterns in all of nature.

Science also assumes that the universe is a vast single system in which the basic rules are everywhere the same. Knowledge gained from studying one part of the universe is applicable to other parts.

A powerful tradition has grown up in science that favors the simple explanation over a complicated explanation of the same thing.

The essence of science is validation by observation. Science is the search for truth through the logical sequence of observation, formation of hypotheses, and testing by experiment where possible, to devise general principals about the working of the natural world.
WHAT SCIENCE IS NOT
Science can only deal with events or things that can be measured or observed. It can not be used to investigate all questions.

There are, for instance, beliefs that cannot be proved or disproved by their very nature (such as the existence of supernatural powers and beings, or the true purposes of life). In other cases, a scientific approach that may be valid is likely to be rejec ted as irrelevant by people who hold certain beliefs (such as in miracles, fortunetelling, astrology, and superstition). Nor do scientists have the means to settle issues concerning good and evil. Answers to these questions must be found in religion and p hilosophy.

This is why the federal court ruled that creationism is a part of religion and not a part of science. Science can only deal ‘with the natural world. This does not mean that scientists do not believe in religion or philosophy. Darwin and Einstein held stro ng religious convictions. Science is one kind of knowledge and religion is another kind.

Science is not technology. Although science and technology are intimately related, they are different. Science is the systematic search for new knowledge; technology is the practical application of the knowledge. Science discovers that electricity can be changed intO light; technology engineers a practical light bulb. A technologist (usually called an engineer) can tell you how light bulbs are made; a scientist can tell you why they give light.
THE METHODS OF SCIENCE
The validity of scientific claims is settled by referring to observations of phenomena. Hence, scientists concentrate on acquiring accurate data. Such evidence is obtained by observations and measurements taken in situations that range from natural settin gs (such as a forest) to completely contrived ones (such as the laboratory). To make observations, scientists use their own senses, instruments (such as microscopes) that enhance those senses,- and instruments that tap characteristics quite different from those humans can sense (such as magnetic fields).

Scientific methods can be grouped loosely into three categories:

Observational: Where scientists make repeated observations of natural events from which they draw generalizations.

Scientists may observe passively (earthquakes, bird migrations, animal behavior), make collections (rocks, shells), and actively probe the world (as by boring into the earth’s crust or administering experimental medicines). The work of Jane Goodall with c himpanzees is an example of the observational method.

Experimental: In some circumstances, scientists can control conditions deliberately and precisely to obtain their evidence. They may, for example, control the temperature, change the concentration of chemicals, or choose which organisms mate with w hich others. By varying just one condition at a time, they can hope to identify~ its exclusive effects on what happens, uncomplicated by changes in other conditions. Scientists identify problems, form hypotheses and test the hypotheses in experiments.

Theoretical: There are scientists who just sit and think i.e., a cosmologist calculating the forces operating in the first millisecond of the Big Bang or a molecular biologist trying to figure out how one molecule can tuck itself into the folds of another.

A scientist may use any one or all of the approaches to solve a problem.
THE NEED TO PUBLISH INFORMATION
Modern science did not become complete until it established one more essential principle-namely, free and cooperative communication among all scientists. Scientists must publish their results in scientific journals so that those results can be reviewed by other scientists all over the world.A new observation or discovery, moreover, is not considered valid, even after publication, until at least one other investigator has repeated the observation and confirmed it. Science is the product, nOt of individuals , but of a scientific community.
SCIENTIFIC IDEAS ARE SUBJECT TO CHANGE
Science is a process for producing knowledge. The process depends both on making careful observations of phenomena and on inventing theories for making sense Out of those observations. Change in knowledge is inevitable because new observations may challen ge prevailing theories. No matter how well one theory explains a set of observations, it is possible that another theory may fit just as well or better, or may fit a still wider range of observations. In science, the testing and improving and occasional d iscarding of theories, whether new or old, goes on continually. Scientist assume that even if there is no way to secure complete and absolute truth, increasingly accurate approximations can be made to account for the world and how it works.

SCIENTIFIC KNOWLEDGE IS DURABLE
Although scientists reject the notion of attaining absolute truth and accept some uncertainty as part of nature, most scientific knowledge is durable. The modification of ideas, rather than their outright rejection, is the norm in science, as powerful con structs
tend to survive and grow more precise and to become widely accepted.
New ideas that do not mesh well with mainstream ideas may encounter vigorous criticism, and scientists investigating such ideas may have difficulty obtaining support for their research. Indeed, challenges to new ideas are the legitimate business of scienc e in building valid knowledge. In the long run, however, theories are judged by their results. When someone comes up with a new or improved version that explains more phenomena or answers more important questions than the previous version, the new one eve ntually takes its place
THE IMPORTANCE OF MATH IN SCIENCE
Mathematics is the chief language of science. The symbolic language of mathematics has turned out to be extremely valuable for expressing scientific ideas unambiguously. The statement that a=F/m is not simply a shorthand way of saying that the acceleratio n of an object depends on the force applied to it and its mass; rather, it is a precise statement of quantitative relationship among those variables. More important, mathematics provides the grammar of science–the rules for analyzing scientific ideas and data rigorously. The scientific method teaches that you run a great risk of being misled if you do not make many observations and examine them as a group. It is unwise to state a general rule on the basis of only one observation. The re is a high probability that you could get fooled.
The field of statistics is; in fiLet, a servant of science because it offers mathematical rules for determining ahead of time how many observations or trials of test results are needed to have a high probability of certainty in your experiment.

Statistics allow us to state how certain we are of a hypothesis. other scientists would put greater weight to a measured event that occurs 95% of the time as compared to an event that occurs only 45% of the time.

BIAS, SAMPLE SIZE AND VALIDITY
When faced with a claim that something is true, scientists respond by asking what evidence supports it. But scientific evidence can be biased in how the data are interpreted, in the recording or reporting of the data, or even in the choice of what dat a to consider in the first place.
Because of the reliance on evidence, great value is placed on the development of better instruments and techniques of observations, and the findings of any one investigator or group are usually checked by others.

Most of what scientists learn about the world is obtained from information based on samples of what they are studying-samples of say, rock formations, bird behavior, pH of soft drinks, cancer patients, whales, or numbers. Samples are used because it may b e impossible, impractical, or too costly to examine all of something, and because a sample often is sufficient for most purposes. In drawing conclusions about all of something from samples of it, two major concerns must be taken into account. First, scien tists must be alert to possible bias created by how the sample was selected. Common sources of bias in drawing samples include convenience (i.e., interviewing only one’s friends or picking up only surface rocks), self-selection (i.e., studying only people who volunteer or who return questionnaires), failure to include those who have dropped out along the way (i.e., testing only students who stay in school or only patients who stick with a course of therapy), and deciding to use only the data that support our preconceptions.

A second major concern that determines the usefulness of a sample is its size. If sampling is done without bias in the method, then the larger the sample, the more likely it is to represent the whole accurately. This is because the larger a sample is, the smaller the effects of purely random variations are likely to be on its summary characteristics. The chance of error shrinks as the sample size increases. For example, for samples chosen at random, finding that 600 out of a sample of 1,000 have a certain feature is much stronger evidence that a majority of the population from which it was drawn have that feature than ~nding that 6 out of a sample of 10 (or even 9 out of the I 0) have it.

Experiments are elaborately designed to exclude extraneous factors that could influence the outcome, but there is always that chance that one has slipped by. As a result, important findings are not often accepted until other scientists have repeated the e xperiment in their own lab and completed their own search for extraneous influences. No amount of testing can render a generalization completely and absolutely valid. Even though billions of observations tend to bear out a generalization, a single observa tion that contradicts or is inconsistent with it must force its modification. And no matter how many times a theory meets its test successfully, there can be no absolute certainty that it will not be overthrown by the next observation.
THE DISCIPLINES OF SCIENCE
Scientific specialties tend to go through an early developmental period, and during their infancy their practitioners can do little more than observe certain chosen phenomena. As the field develops, it accumulates enough observations to permit astute thi nkers to begin to perceive regular patterns in the phenomena that are observed-patterns that often betray a hidden force, mechanism, or process. Scientists then begin to formulate hypotheses or, to put it more plainly, try to imagine what might be going o n behind the scenes. Having done that, they try to think of experiments that will test their hypotheses.
Chemistry and physics are two of the oldest sciences, and perhaps the two most developed. They have more laws, theories and mathematical formulas than the other sciences.

Chemistry and physics have searched for centuries for patterns in nature. Each has well- developed methods of testing hypotheses. Both have been in existence long enough to find hypotheses that predict the outcome of an experiment correctly every time. Hy potheses that do this become laws or rules. The phenomena dealt with in chemistry and physics usually perform so neatly that they can be described in mathematical terms. We have found that the force of a moving object is the object’s mass multiplied by it s acceleration.

The science of biology began its major period of development much later, and not until the twentieth century was it apparent that certain phenomena in living organisms behave with anything like mathematical precision. ‘As a result, much work in the life s ciences remains in the early stages of observation, and the search for patterns in the observed phenomena is still young. Those areas of biology that are closely allied to chemistry-biochemistry and molecular biology, for example are today approaching the degree of mathematical precision of the older sciences. This is not true of ecology, evolutionary studies or developmental biology. These recent branches of biology must settle for hypotheses, theories and laws that can be stated in imprecise terms.

Earth science is a younger science. It is not as well formulated as the older ones except where it deals in chemistry and physics.
CONTENT VS METHODS IN SCIENCE EDUCATION
To be literate in science, students need both content and methods. They need a background in science content on which to build. New students must learn many definitions in order to speak the language, but there is such a large body of knowledge it poses a problem. Science education today is faced with too much content. We must decide which are the important concepts our students need at a particular stage in their studies and what should be eliminated.
Science is an important process that relies on the use of scientific equipment. Students can best understand science by doing science. They can understand it by using telescopes, microscopes, computers, temperature probes, pH meters, geiger counters, rheo stats, oscilloscopes, lasers, air tables, spectrophotometers, glassware, electronic balances and the other tools of science in observing, classifying,ing, inferring and experimenting in class.

Science education in most cases has not practiced the use of higher order thinking skills or the scientific processes. It has relied on content-lecture, reading the text and tests to weed out all but the most determined. This must change. Today, we need a balance that uses scientific processes, higher order thinking and decision making skills along with our traditional scientific content. With these and an adequate amount of the proper scientific equipment, we can raise the test scores of all students.

NATIONAL TRENDS IN SCIENCE EDUCATION
Project 2061 of the American Association of the Advancement of Science recommends the following actions for science education:
1. Interdisciplinary science, rather than discrete packages
of biology, chemistry, physics and earth science
2. Less content, rather than more
3. Emphasis on ideas rather than facts, concepts rather
than terms
4. Integration of mathematics at every level of science
(including the life sciences)
5. The inclusion of communication and decision-making
skills as a part of science, not merely as add-ons

The National Science Teachers Association is advocating that interdisciplinary science be taught all six year from the 7th grade to the 12th grade. Students would be exposed to twelve years of science as opposed to the ten or less years that most receive now.
STUDENT SUCCESS IN SCIENCE FAIR PROJECTS

Most science fairs have an abundance of models and displays. Models and displays have their place in the beginning levels of science. They help students learn how to display their exhibits so their audience can understand a scientific principle. Few of th e local science fairs have examples of scientific research. Even the best stabs at research are lacking in library review of the topic, observations, formulation of hypotheses, use of control and experimental groups and recorded data. The majori ty do not collect enough data (nor apply math to that data) in order to give any strength to their conclusions.
Students below college level should use either the observational or the experimental science method in their science fair projects. The following are some examples of each:

Observational method: A student has been observing Mockingbirds for some time. He decides he wants to investigate where the birds build their nests most of the time. This means he must observe Mockingbirds in many different locations during nest bu ilding time and record his observations. The student’s results need to be displayed in graphs. The average height from the ground needs to be calculated and a description of nesting sites given. This kind of work generates sufficient graphable data.

Another student decides she wants to know if ants travel at a slower pace on cloudy days than on sunny days. The student has to select several colonies of the same species of ants, observe them on sunny and cloudy days and record their respective speeds o ver the same selected distance. She also has to worry about the other variables that could affect the ants such as temperature, humidity, wind, degree of cloudiness, etc. The student needs to average the rate of travel for each group of ants (cloudy day r ates and sunny day rates). These two averages could be compared. There are statistical tests that could be done to check to see if the two averages are significantly different form each other.

Experimental Method: A student wants to test the effects of various drinks on an iron nail. He could place nails in glasses of Coke, 7-UP, Pepsi, lemonade, tea and milk for a week and check the results, but since very little data would be collected the results would not be very strong and could be biased. Now if the student places 10 nails in 10 glasses of Coke and 10 nails in all the other kinds of drinks for a week his results will be significantly stronger. The greater the sample size the smalle r the effects of random variations.

He should also check to see that he is using the same volume of liquid in each of the glasses and that he has the same size nail for each glass. At the end of the week each nail needs to be weighed.

To set up a control and experimental groups he could compare each nail in the experimental group (drinks) with a nail left in glasses with a known non-reacting liquid. He could average the results from each type of drink and compare it to the non-reacting liquid group, graph his results and draw conclusions. Again the more data gathered the stronger the results.

Science fairs are opportunities to involve students in the use of these scientific methods. Students, however, must be taught these processes in class and judged by them at the fairs.
REFERENCES

Science for All Americans, Project 2061, The American Association for the Advancement of Science. 1333 II Street NW, Washington, D.C. 20005.

My main concern is to explain why some tea leaves sink and some tea leaves come to the surface in boiling water.

Preliminary facts
I can say that the cause of this phenomenon is Brownian movement and convection. We discuss Brownian movement later. But, first of all, it is necessary to define what convection is.

Convection is one of types of heat-exchange: transmission of energy in liquids and gases by means of currents. Natural (free) convection takes place in gravitation field by irregular heating (from below) liquids and gases. The heated substance moves relatively to the less heated substance in opposite direction to the direction of gravity as resultant force of gravity and Archimedes directs upwards and equals by module F=pgV, where p = density difference between heated substance and environment – the less heated substance; V = volume of heated substance; g = acceleration of free fall.

By convection the substance temperature becomes even. The convection speed depends, in particular, on temperature difference between layers and heat-conduction of substance. By forced convection transference of substance layers takes place with the help of a pump, a mixer or some other similar device.

Equipment

• A transparent vessel with boiling water
• Tea leaves

Procedure

1. To take an empty cup (in this case it is better to use a transparent vessel).
2. To put in the cup some tea leaves of different sizes.
3. To pour boiling water into the cup.
4. To observe movement of tea Leaves during 2-3 minutes.

Results

The aim No 1 Solution
The first idea that has come to my head was the idea about interaction of water particles, i.e. water molecules had effects on tea Leaves. In boiling water molecules move rather quickly by complex trajectories. Some molecules hit the tea leaves, so some tea leaves now come to surface now sink.

The aim No 2 Solution
The No 2 Solution consists in convection. How does it take place? We have boiling water. The upper water layer becomes cold more quickly than the lower one, i.e. the Lower water layer is more light than the upper one. By this process the lower water layer is forced out to the place of the upper layer. The shift of water mass took place. Then this process takes place one more time. So, tea leaves come to surface and sink.

The aim No 3 Solution
In boiling water some tea leaves, at first, sink, then give brown color to water at the bottom, then some tea leaves come to surface. This process is the very question. Why does it take place? To solve this question I think it is necessary to follow the very process, step by step. Some Leaves sink but not at once. This takes place because water stretch has effect on tea leaves. The first to sink are the leaves which have the less area, volume (in cold water or in indoor temperature water the Leaves don’t sink because the upper water layer prevents this process. This layer is like a film). Then at the bottom of the vessel, under the hits of water particles the brown color emits out of tea Leaves and spreads in all water. It is clear that tea Leaves which are at the bottom of the vessel have small density. The water loses its warmth because of vapor and because tea Leaves become warmer (the density becomes more less). Besides the warmth comes into air. The water, gradually, cools, so the density rises. The leaves, that are at the bottom, come to surface because their density became less. But only those tea leaves will come to surface which have the less area, volume. After all only some leaves come to surface because small leaves are covered by bigger ones. The larger leaves need more warmth and energy out of water which it loses. It appears, that the leaves which have the smallest volume sink and come to surface.

Conclusion

This experiment has some nuances, i.e. the solutions have their shortcomings and minuses :

Solution No 1 minuses

This solution has one nuance: when water molecules move with high velocity, there is a great number of water molecules, they move from different directions. So, tea leaves don’t come to surface or sink but dance under condition that water particles have effect on the leaves. Let’s remember English botanist R. Brown. Through an ordinary microscope he looked at flower pollen which was spread on water. Pollen particles as if were dancing in the water, because water particles had effect on them. Therefore, solution No 1 is unsteady.

Solution No 2 minuses

By No 2 solution it is evident that water masses shift each other when more around. It appears that leaves move like water, i.e. tea leaves more under the stress of water masses, all leaves together, not separately. Our tea leaves must not come to surface and sink together.

Solution No 3 has 2 hypothesis

1. Tea leaves lose heavy color and come to surface, after that they get wet much more and sink.
2. Water quickly increases its density after cooling of Leaves and water. The conditions of floating are changed – leaves can come to surface. The heat-transference from water to leaves is possible.

So, I have 4 solutions for this problem

1. Brownian movement.
2. Heat-currents of water, Leaves take place in them.
3. Leaves lose heavy color.
4. The water density increases.

With the help of this experiment we can study such divisions of physics as convection, heat-transference and particle movement in physical bodies, and, also, diffusion (Here diffusion takes place in wetting tea leaves).

Let’s check the solutions

• We can check participation of tea leaves in water heat-current – to add in water some dye-liquid (ink) and to decide if the tea leaves movement is similar to dye-stuffs movement.
• We can make tea leaves devoid of color already.
• We can make tea leaves in cold water.

Improvement

Science is such a thing in our life that it has no borders and has thousands answers on each particular question. It is clear that there are many hypothesizes concerning this experiment. I’d like to know and study them. For example: I could not explain how vapor has effect on tea leaves. I am interested in many other questions.

My investigative question was: Does the temperature of water affect the time it takes for the water to freeze?

Hypothesis

Materials

1. Water
2. 3 containers (similar)
3. Candy Thermometer (to measure temperature of water)
4. Watch (to measure time it takes for water to freeze)
5. Tablespoon (to measure the amount of water to put in the container)
6. Microwave (to heat water)
7. Freezer (to freeze water)

Research/Sources of Information

Before I start the experiment I need to find out:

• the temperature at which water freezes and boils
• the temperature of the freezer
• the room temperature
• the procedures and materials.

I also did the following experiment as background research.

1. I decided to use a clock timer to measure the time it takes for the water to freeze and a paper knife to feel if the water in the bottles has frozen and become solid ice.
2. I took four white glasses that were all the same kind.
3. I poured one cup of tap water into one glass and let it sit there so it could become room temperature water.
4. I used a different glass to make boiling water. I used one cup of water and I put it in the microwave to boil.
5. I had kept the water in the microwave for three minutes. When I had taken it out the water was boiling. Before I had put the water I had made a prediction that the water would turn into steam. When I took the water out it hadn’t turned into steam that showed that my prediction was wrong.
6. I was going to use a thermometer but then I realized that the thermometer was only for humans. The thermometer would only go high as 106 F and boiling water is 212 F.
7. Also, I realized that the timer I had picked won’t work because it goes down and I need one that goes up.
8. So I only put in two glasses of water in the refrigerator and I didn’t time them. This helped me identify the correct procedures and instruments to use in my experiment.

I used the book Science with water to help me identify the different temperatures at which water boils and freezes.

Vocabulary

The temperature of the water in four bottles at the start of the experiment is the manipulated variable. The time it takes for the water in the four bottles to freeze is the responding variable. The conditions of the experiment are the controlled variables. In my experiment, the controlled variables are:

1. the amount of water in the four bottles
2. the kind of bottles that are used
3. the temperature of the freezer.

Experiment

1. I took 3 bottles of the same kind and size.
2. I labeled the three bottles as #1, #2, #3.
3. In #1 I put one tablespoon of water. The temperature of the water was at room temperature.
4. In #2 I put one tablespoon of water. The temperature of the water was hot (130o F).
5. In #3 I put one tablespoon of water. The temperature of the water was very hot (200o F).
6. I placed the three bottles on a tray and put it on the top shelf of the freezer.
7. I noted the time it was 10:54 am. I set the stop-watch to beep every five minutes so I could check the bottle
   

   Results

   The following table shows the time at which the water in the three bottles froze on the top:

   Results

   Bottle #	Amount of Water	Temperature of Water	Time put in freezer	Time ice forms on top	Time taken to freeze
   #1	1 tablespoon	70 F (room temp)	10:54 am	11:45 am	51 minutes
   #2	1 tablespoon	135 F (hot)	10:54 am	12:00 pm	1 hour 14 minutes
   #3	1 tablespoon	200 F (very hot)	10:54 am	12:15 pm	1 hour 29 minutes

   These results can be shown in a graph like below:

   

   Conclusion

   The results of my experiment showed that temperature of water has an effect on the time it takes to freeze. My experiment proved my hypothesis – the higher the temperature of the water, the longer the time it takes for water to freeze – and showed that my hypothesis was correct.

   ---

   Optional

   How did I come up with my project idea?

   I picked it off the list of questions given by the school as the easiest experiment to do. I was not really interested in the effect of water temperature on freezing time. It might have been more interesting to see the effect of temperature on other liquids such as wine and oil.

   What did I learn from my experiment?

   I learned a lot of things. I have listed them below.

   How close were my hypothesis and conclusion?

   My hypothesis and conclusion were the same.

   Did I learn anything new from my project?

   Yes. I learned a lot of things in doing this experiment. They are:

   • I learnt how to be specific with my work
   • I learnt how to make a table
   • I learnt how to make a graph
   • I learnt to take pride in my work
   • I learnt to make a bar graph
   • I learnt to take my time.
   • I learnt how to use a thermometer.
   • I learnt how to read a thermometer.
   • I learnt to revise my work.
   • I learnt how to spell new words.
   • I think the scientific method is hard.

   What was the most interesting part of my project?

   Playing with the water and measuring the temperature.

Jack Hanna has become somewhat of a household name. Children all across the country tune in to watch his escapades in the syndicated weekly television show Jack Hanna’s Animal Adventures; night owls stay up late to watch him swap jokes and show off exotic animals with David Letterman; visitors to the Columbus Zoo and other animal parks laugh and learn as he teaches them about animals and the importance of conservation. His Web site proclaims, Jack Hanna is “every person’s television zoologist.”

Hanna’s national celebrity gives him the unique ability to bring his message of animal and wildlife conservation to a broad segment of the population. He uses his frequent guest appearances on shows such as Good Morning America and Larry King Live, as well his many onsite visits to places such as Sea World of Texas, to share his enthusiasm for wildlife with a large and growing audience of both children and adults. “I’d rather entertain and hope that people learn, than teach and hope that people are entertained,” he says.

Clearly, Jack Hanna is more than just an entertainer. Director Emeritus of the Columbus Zoo in Ohio since 1993, he is still very involved with zoos and is a member of several conservation societies and professional associations, such as the National Alliance for Species Survival, the American Zoo & Aquarium Association, and the Explorer’s Club. Since coming to the Columbus Zoo in 1978, Hanna has worked with his staff to create a program that is both entertaining and educational, one that encourages students to become actively involved in learning about and preserving nature. He finds that a visit to the zoo, especially during a child’s early years, provides an opportunity to experience nature and to learn about the animals in a way that cannot be accomplished through books or other media. “The world is the true classroom,” he explains. “The most rewarding and important type of learning is through experience, seeing something with our own eyes. A visit to the local zoo, museum, nature center, factory, or even a business will probably stay in the student’s mind far longer than if he or she were to study about it in a book.”

A Living Classroom

The visiting of zoos, Hanna notes, is the largest family recreation activity in the United States. Last year, more than 125 million people visited the country’s 160 zoos; at the Columbus Zoo alone, at least 150,000 children came through for a visit during May, which is the month many schools choose for making field trips. The appeal for families-and for schools-lies in the fact that a trip to the zoo is both fun and educational: “A zoo is much more than a home for animals,” Hanna says. “It’s a living classroom.”

In this living classroom, the excitement that children bring involves them in learning that is multisensory and multifaceted, so that they gain a deeper appreciation for and understanding of what life is all about. Students can actually hear the low rumblings of an elephant or touch a snake’s smooth skin; they can look at the bones and teeth of a tiger and see how big they really are. “You can’t see this in books; you can’t get the atmosphere from a CD-ROM,” Hanna stresses. An example he cites is that even though a child may read about how tall a giraffe is and how it has the same number of vertebrae-seven-in its neck as a human being, the knowledge becomes much more real to that child when he or she actually sees a giraffe and realizes just how long that neck really is. Similarly, reading about the 40,000 muscles in an elephant’s trunk isn’t nearly as memorable as witnessing the versatility afforded by those muscles as the elephant picks up items as small as a kernel of corn or as giant as a one-ton log.

Focus on Learning

Even though reading books and viewing CD-ROMs can’t replace the real-life learning that goes on at the zoo, they can be used successfully in classrooms to prepare students for their visit. Hanna suggests that teachers have their students read up on whatever topic they are going to study, look on the Internet for information to supplement more conventional resources, and then write reports or essays that they can review and revise when they return to the classroom after their visit to the zoo. It is also a good idea to focus on one or two main learning topics-such as a particular group of animals or a specific adaptation, like defense mechanisms-and go over what students should look for while at the zoo. Focusing on specific learning objectives gives students clear parameters and more definite expectations. Subsequent visits can target different exhibits or topics, so that the learning process can be ongoing. “Every time children come to the zoo, they appreciate living things and learn something new about animals,” Hanna says. This applies even to himself: after 26 years, he says he still learns something new about animals every time he goes into the zoo or on safari.

Teachers should not forget some of the more practical considerations involved with a field trip to the zoo, such as stressing the types of behavior that will be expected of students while there. An important step in readying them is to make clear that they will be entering the animals’ homes and need to treat them with respect-the same kind of respect they would expect of visitors to their own homes. Students should also be oriented as to the layout of the zoo: where the restrooms are, where the first-aid station is, and where to meet for lunch. A map of the zoo would help them get their bearings.

Many zoos offer scheduled events and exhibits that teachers and parents should be aware of before taking their children on a visit. For instance, during the summer the zoo keepers will often give lectures about specific animals, such as the elephants or gorillas. Children also enjoy watching the animals eat, so finding out when feeding times are helps them learn a good deal about the animals’ feeding habits. Most zoos offer special programs, such as bird shows, especially during the spring and summer months. Hanna suggests that teachers contact their local zoo prior to their visit and ask for information on special and permanent exhibits, schedules, and pre-visit materials to review with their students.

Lessons for a Lifetime

Animals and nature aren’t the only subjects in the “curriculum” taught by a zoo: “As children get older, they learn that the zoo is part of their community,” Hanna explains. “They learn about volunteering-half of our zoo is supported by volunteers.” Visitors can also explore the variety of career choices available at a thriving zoo-contrary to popular belief, not everyone who works at the zoo is involved with animal care! There are almost 20 different careers operating in a zoo, in such fields as public relations, education, marketing, waste water treatment, landscaping, graphic design, and construction.

As children continue to make visits to the zoo and learn more about animals and conservation, Hanna notes, they become more aware of the interconnectedness and the interdependency of life. His goal is to make them aware of the importance of preserving that life, and the only way to do that is through education. He gives the example of the African elephant: in 1975 there were 1.4 million of them in the wild, and now there are less than 40,000. “The most important thing is to preserve the world we live in,” he says. “Unless people understand and learn about our world, habitats, and animals, they won’t understand that if we don’t protect those habitats, we’ll eventually destroy ourselves.”

When I had the opportunity to talk with Dr. Rob Semper, Executive Associate Director of the Exploratorium, my first order of business was to ask if that pin screen is still there (it is). Dr. Semper has been with the Exploratorium for more than 20 years, and he enjoys watching students and adults become engaged with the museum’s exhibits. The goal of the Exploratorium, and other science centers like it, Semper says, is to stimulate visitors to become active participants in their own learning. “Places like the Exploratorium are, in a sense, collections of ideas and points of view about nature as much as they are collections of objects,” he says. “In a way, they are collections of experiences. The visitor is really in charge of their visit, and what interests them is what drives their visit.”

Windows of Perception

The Exploratorium was started in 1969 at around the same time as other science centers were opening across the country. The premise behind these centers-there are now more than 200 of them-is to encourage visitors to explore nature on their own. When the Exploratorium first opened, its exhibits were mainly related to human perception, such as seeing, hearing, and touching. As it grew, the exhibits expanded to include more of the underlying science concepts involved with perception, including light, color, and sound waves. There are now more than 500 exhibits that cover nature and science, and 20 to 25 new exhibits are built each year to add to the collection. Ideas for these exhibits come from the Exploratorium’s staff of scientists and artists, but also from visiting teachers and other interested members of the public. “We’re a place not only of exhibits but of constant exploration in new ideas in science, and visitors are invited to come along with us on these journeys of exploration,” Semper says.

Each year, the Exploratorium welcomes more than 600,000 visitors, and some of the most popular exhibits with students, Semper notes, seem to be those that deal with light and color. Sample exhibits on images and light deal with the nature of light and creating images, how light gets perceived, and some aspects of animal vision. “The perceptual exhibits are big favorites because they can tell you a lot about yourself as well as what you are seeing,” he explains. “For example, not everyone sees the same thing; there is a great variation in how people see color or color differences.” One way students can physically experiment with light and color is to shine a light through a prism and different color filters and observe how the light is spread out in a colored spectrum.

This tactile interaction with the exhibits is a key element in giving students a good grasp of what goes on in science and nature. The Exploratorium is not a museum where visitors stroll past interesting objects and admire them with their hands clasped behind their backs; no, here they are expected to actively explore and work with the materials in front of them. “Our exhibits really require the visitor to do something,” says Semper. “You have to be an active participant-you manipulate things and try them out for yourself to really satisfy your own questions.” At one exhibit, for example, students can see how nerve cells work by stimulating actual nerve cells and watching the electrical response. At another, they learn about DNA by manipulating models that illustrate the double-helix construction. A staff of Explainers, mostly high school students from San Francisco, is on hand to help people interact with the exhibits, asking and answering questions. Interestingly, most of these Explainers, Semper notes, are not necessarily exemplary science students, yet after working for several months at the Exploratorium they have gained a wealth of knowledge about science and their own learning process.

Role Models of Inquiry

“The most important thing is not so much learning a particular fact or idea, but rather stimulating in students the notion of questioning, of even being interested in the first place,” Semper says. He encourages teachers to bring their classes in at the beginning of the year rather than the end because it can generate an interest and a curiosity that can help drive discussions all year long. Hands-on interaction with science and nature can give children a visible and visceral understanding that can serve as the foundation for what they learn in the more formal classroom settings.

One way teachers can help make a trip to the Exploratorium successful is to come ahead of time and visit the museum without their students to get a sense of what is there. That way, the teacher has personalized the museum to an extent and is able to offer students a base of common knowledge to familiarize them with it as well. Some teachers have even developed worksheets based on the exhibits that they can have their students use while there. When at the museum with their students, teachers should participate with them as learners, even if that means not always knowing the answers to questions. “It’s important for students to see teachers modeling the process of exploration,” Semper explains

Another possible preparatory activity is to have students make one of the exhibits in The Exploratorium Science Snackbook: Teacher-Created Versions of Exploratorium Exhibits, which is a compendium of modified exhibits that have been adapted to be less expensive and easier to create. After building some of the exhibits in the book, the students come to the museum and examine the exhibit after which their creations are modeled.

The Exploratorium offers more formal training and professional development for teachers at the K-5 level and the 6-12 level. Teachers from beyond the San Francisco Bay Area are encouraged to participate alongside local teachers in three-week-long summer workshops and follow-up activities. The K-5 program, called Institute for Inquiry, is designed primarily for professional developers and helps participants develop their skills in providing inquiry-based science professional development in their home districts. The Exploratorium Teacher Institute works with 6-12 grade teachers to develop teaching skills for science that are specific to the exhibit content at the museum.

“The exciting thing about informal education is that it can happen at almost any time, at places that are available to families, to students, and to teachers,” Semper says. “Science centers and museums are places people come to all the time; they are part of the community educational enterprise that can be used in many different ways. People come here with a well-developed base of knowledge and ideas. But it is often the opportunities of surprise that become the key educational events.”

Objective
To learn about static electricity.

Materials
Two balloons, Tape, Two four-foot strings, and a Piece of dry wool cloth.

Procedure
Inflate the two large balloons and tie them to the ends of the strings. Hang these two balloons from the ceiling with a piece of tape. Adjust the length of the strings so that the balloons are barely touching each other. With the piece of wool cloth, rub each balloon for several seconds. What will happen when you let the balloons hang together freely? Will they pull together or farther apart?

Conclusion
The balloons are pushed away from each other as if there is a force there that can not be seen. This happens because each balloon has an electrical charge of static electricity. Because the charge of the electricity is the same on the surface of both the balloons, the balloons are repelled, or forced apart. Because the balloons are not very heavy, little charge is needed to separate them.

Objective
To learn about the characteristics of water.

Materials
Clear glass, and paper clips.

Procedure
Fill the glass with water until it is completely full. At this point you can predict, or guess, how many paper clips you will be able to put into the glass until the water over flows. Start placing the paper clips into the glass, but make sure you count them as you put them in. How many were you able to place in the glass before the water overflowed? How close was your guess?

Conclusion
If you guess a number from ten to twenty, you were far from the correct number. Once you tried it however, you realized that the cup of water could in fact hold hundreds of paper clips before it over flowed! This is because the water forms a thin skin around the water. Look at the glass of water from the side. You can see that the water is actually over the top of the glass. The layer of skin keeps the water from over flowing.