Natural Science - Year I

Chat times for 2017-2018
Tuesday
9-10:30am ET/6-7:30am PT


Dr. Christe Ann McMenomy

Student Survival Guide for the Natural History Course - Year One

Or: How to survive a science course


Why Study Science?

At the heart of all science is something called the scientific method. The simple version of the scientific method is based on the idea that the objective reality of the universe can be determined by carefully observing phenomena, recording appropriate measurements, then studying the data from these observations for patterns that can be used to describe the general behavior of classes of natural objects. When we can control the circumstances of the observations, we are performing experiments, but often we cannot control all the factors before we make observations. There are scientists who believe that the only valid scientific data is that which comes from controlled experiments; in their view, most of astronomy, meteorology, geology, and many parts of biology are not rigorously scientific (but most physics and chemistry are). Since this is a natural science course, in many cases we will be looking at theories formed outside the experimental tradition! One of the things you will need to decide is whether this affects the validity of the theory.

Man's search for patterns led him to keep track of many phenomena from very early in recorded history. Heavier items make a deeper dent in the earth when they impact the surface. Some metals, in chips small enough to float on water, will spin round and orient themselves toward the Pole Star. Water, when it turns to steam, expands (it also expands when it turns to ice!). The planets move in complex patterns that repeat only over long periods of time. Plants and animals have similar structures that may (or may not!) function in similar ways.

When scientists find similarities between objects, or patterns of behavior that repeat with little variation, they want to study the similarities to see if there is some common cause behind them. When the scientist finds a reasonable explanation, he or she proposes a hypothesis, a testable statement about the phenomena. Hypotheses that stand up over many repeated observations are combined to make theories; distillations of theories that have no known exceptions may be called natural laws.

Our expression of physical laws are not immutable, despite the name. As we move through history, we will look at many theories that were considered unshakable physical law, but which were later challenged by new observations. In this course, we will examine not only the theory content but the conditions under which a society accepted or rejected that theory.

Science is a human activity. One of the objectives is to learn as much as possible about the objective universe, the one that exists without our interpretations. As we study science this year, you will want to ask how non-science factors like personal ego, dominant theories, philosophies, and regions, influenced the theories of science.


The Science Course Online

Science classes are frightening for many students. They anticipate difficulties with the concepts, with the details, and especially with the math. But science is just one way of thinking about the natural world around us, and anyone can learn to think like a scientist. Don't waste energy worrying about your ability to learn the material; use your energy to learn it! Once you get the hang of it, you'll be able to discover, understand, and appreciate the complexity of God's creation better. You will also be better prepared to take your place as a steward of that creation.

Review the prerequisites for the course. These are the concepts and math skills that you should have mastered in order to succeed in learning the material. The math prerequisites for this course are described in the FAQs page (there aren't a lot!). If you have any questions about your readiness for the course, be sure to ask for help during our first session. I will arrange to work with you so that you can gain the required skills quickly.

Every science course has as its main components lectures, reading assignments, labs, and lots of homework to prepare you for taking quizzes and exams. In addition to these, our online course has this website, the Moodle, and e-mail to provide the functions that would normally exist in talking to your teacher face-to-face, or looking at a bulletin board or whiteboard. Keeping track of all the components can be at daunting task, especially at first, so plan to spend some time becoming familiar with the course website, your texts, and the Moodle. Once you have mastered the mechanics of using these tools, you can concentrate on learning the material that they contain.

Why are there so many parts to the course? Well, part of the reason is that you learn in many ways. You memorize facts, you comprehend relationships, and eventually, you understand concepts. You learn by reading, by seeing pictures and graphs, by watching demonstrations of processes, by participating in discussions, and by applying what you are learning to specific situations in the homework and labs. You "cement" what you've learned by teaching others. The organization and materials of the course require that you take all these approaches.


Managing Your Time

This course has a lot of components. Read the Procedures page carefully, so that you understand what will be expected of you in class sessions and as you read and do your worksheet questions. Copy down the checklist of all the components and look at the possible ways you could pace your time, and make your own plan. Stick to it for several weeks, then modify it to suit your own study habits and other commitments. The key to this course really is self-discipline; you will need to determine how much time to spend on memorizing facts, understanding concepts, completing worksheet assignments, and (if you chose the lab option) performing the experiments.

Regardless of how else you schedule your workload: try to do your assigned reading as early as possible. This allows you to think about the questions and material, review it in your mind, and absorb it more critically.


Web Lectures

Rather than take our precious chat time by lecturing to you, all unit lectures are posted to the site. You need to read these as well as the text. The lecture pages have

  • a key to the time period and geographich area or area of science involved
  • a list ofindividuals involved in creating the scientific theories discussed in thye unit
  • a list of related history or science topics
  • an outline of the lecture
  • the reading assignment
  • the lecture itself
  • lists of discussion questions to prepare for chat
  • optional website readings for your copious free time

As you read the web lecture, make notes on anything that puzzles you, and be sure to raise your questions in class.


Getting to Know the Textbooks

There is no textbook for this course -- we do web readings, and our first session will discuss those.


Doing Homework

Homework is not merely useful, it is essential for mastering the concepts of a science course. Just as we test theories by applying them to experimental situations, you test your understanding by applying it to specific situations. You will know whether you understand a concept if you can use it to solve a "real-world" problem, and when you can teach it to someone else.

We use both doing and teaching techniques in this course. You will have a worksheet of questions to complete for each unit. You will be able to check your answers against the posted answers the day after each worksheet is due. You should spend the time to compare the two until you understand not only the material used to answer the question but the level of detail used as we.. From time to time, you will need to post a report topic or worksheet answer to the Conference Center. This gives you the chance to teach something you have learned to your fellow students.

While it is not a requirement for the course, you can and should spend some time explaining concepts that we cover to your parents or to an interested sibling.

Essay questions

Most of your homework general questions don't involve calculation. Essay questions ask you to explain a concept in words, sometimes more words than less.

Try to answer all questions in complete sentences; this means you have to write at least one sentence for each question. A one-sentence answer is appropriate for short questions like "Who first formulated a universal law of gravity?" If you answer the question "Isaac Newton", you don't formally associate the achievement with the person. Verbalizing it will exercise your mind and help you remember more: "Isaac Newton first expressed a universal law of gravity." If you add a bit of contextual information (not a lot!), you'll associate that as well — which helps on examinations: "Isaac Newton published the first mathematical expression of the universal law of gravity in 1666."

In questions that require more information, be prepare to cite calculation information as well as concepts, or give examples.

For example: A projectile has the least speed at which point in its path?

A good answer will be grammatically and syntactically correct, using proper English, as well as contain the correct information. It will cover more than one point in supporting its argument.

Assuming that the projectile is shot at an angle so that it rises with an initial velocity and constantly decelerates under the influence of gravity. It will eventually slow down, stop, and return to the surface. At the top of its arc, its speed will be zero, since it is no longer moving up and has not yet started moving down. This is the point of least speed. [Note that this is not the same as least velocity, which takes direction into account. For least velocity, the answer will depend on what coordinate system is used.]


Getting the Most from Chat

Chat sessions are 90 minutes. Plan accordingly, and take a break just before class starts. Do some stretching, go to the bathroom, eat or get your drink and snacks before you enter the classroom. Be sure to try to connect to your ISP and check mail 10 minutes before class if possible, in case any late notices have been sent by the teacher. Give yourself the extra time. High traffic on your ISP or the school server can slow you down and force you to miss the first 5 to 10 minutes of class.

If you have not already done so, post your assigned essays the Moodle before the start of class.

Bring your notes, worksheet answers, and paper and pencil to class. If you are comfortable using a desktop calculator and taking notes in a text utility like Notepad (available as different applications on both Windows and Macintosh), you can use those. Take notes during class. If you are logging, you do not need to document things the teacher or other students say, but it is useful to note your own questions and observations as they occur, so that you can study them later.

Take part in the discussion. Ask questions as they occur to you (or note them and ask them at the end of class).

Chat sessions in the sciences often involve discussion of mathematical calculations and chemical formulae. In IRC, we were unable to use formatted text. That is not the case here, but it may take awhile to get used to then new chat features. Typing HTML tags may take longer, so if I'm in a hurry, you may see me use underscore (_) for subscript and up-arrow (^) for superscript. The term x_1 ^2 means "take the value x-sub-1 and square it". You may be more used to seeing this written as x12. Likewise, the formula for water would be H_2 O, or H2O.

Print the log out. As soon as possible after class, review the log and make notes on it about any points that bother you, and be sure to ask about these in our next session. Mark important points for review later. Save the log to review before the next session and before semester examinations


Quizzes

All the Natural Sciences examinations (quizzes, midterms, and finals) which I use to evaluate your understanding and progress in Natural Science will be drawn from the homework questions in the text and study questions in the worksheets. It is very important that you complete the homework problems, study questions, and any reports assigned to prepare for the exams for this course.

There will be an online quiz for each unit, which will be posted at Moodle when we have finished discussing the material in the chapter. These quizzes include 10-15 multiple choice questions and are timed. You can take this quiz only once while it is open (during the week following our discussion); if you miss a quiz, or want to review, you can take once during the grace period at the end of the semester. Quizzes are always closed book.

Most of the questions on the Natural Sciences midterms and finals which I use to evaluate your understanding and progress in science and its history will be drawn from the online quizzes and homework. It is very important that you do the assigned reading and worksheet questions, and take the online quizzes to prepare for the exams for this course.


Exams

Start your review two weeks prior to the scheduled examination.

Read through the list of scientists at the top of each history unit. Review the science points. Be able to map scientists to their discoveries.

Go over your worksheet questions and answers; determine any areas where you have questions or don't clearly understand the ideas.

Review the chat logs, and go over your notes.

Review your performance on quizzes, and make a list of the concepts with which you are still unfamiliar or which still puzzle you.

There will be two major exams (semester finals), one in January and one after the last lecture, which you will take during the first week or so in June. These will be mailed electronically to you, and you will take them with your parent or other responsible adult as proctor, and e-mail your answers back to me. Both exams contain a section where you will match scientists to discoveries, a large multiple choice section with questions drawn from the online quizzes on basic science concepts, and essay questions.


Study Groups

Not only may you study together, but you should study together — remember that explaining or teaching what you just learned to someone else is one of the important techniques of learning! You may also work together to discuss and frame answers to the worksheet problems ... but be sure that you can answer them on your own afterwards, since you cannot work as a study group on quizzes or examinations. I encourage you to set up a regular time to exchange messages or use the general forum to discuss issues.


Doing Labs:
The Scientific Experience

One of the basic methods of science is to secure documented observations of periodic or common events in order to make some general summary about the behavior of natural objects. We can do this in several ways.

  • Directed observation

    All observations of stars and planets, most observations of plants and animals in their native habitats, and many observations of geological specimens and meteorological events, are "field" observations. The situations must be allowed to occur without human direction, either because such direction is impossible (we can't control when a star will go nova), or because human intervention would interfer with the observation (we don't want to feed animals if we are researching their eating habits in the wild). The best we can do is make many observations of phenomena that are as similar as possible.

  • Laboratory-based experiments

    Laboratory-based observations are much more tightly controlled. Specific techniques and equipment are used for particular kinds of data collection. The experimenter can often vary only one factor at a time to see how it affects other dependencies. This allows many experimentalists to compare their results easily.

  • Surveys

    Frequently, research in one area reveals a tendency for a particular phenomena\on to behave a certain way. Rather than simply starting to observe the phenomena anew, one may choose to go back through past observations, looking for the same patterns or evidence of how nature behaved in similar circumstances. Surveys of historical data are common in weather studies, where such records exist for periods of 100 to 150 years, and in astronomical observations.

    Surveys and re-examination of astronomical data are very common, since telescope plates taken in the 1920s by a researcher interested in a single star or event will contain data relevant to other events as well. The earliest photograph showing the growing magnitude due to the supernova of 1987 was taken by an Australian astronomer who was looking for something else entirely in a different part of the Magellanic Cloud. After checking the photo for his own star, he went to bed...and so missed being the "discoverer".


Lab Reports

Parents and students always ask at the beginning of the year "How do you want me to write the lab report? Can you give me an example, or a form to fill out?" I have a hard time with this question, because it moves lab work from the arena of doing science to the arena of getting a grade. This shifts the emphasis from having your own valid experience of the scientific process, whatever happens while you follow the lab outline, to striving for some "correct" experience that exists only to show you what someone else has already figured out, and failing when you don't get the right results in the right units to put in the right blank on the page.

Real science doesn't work that way. Certainly, professional scientists do have expectations about what they will find when they set up a situation and watch observe it for awhile, but they have to be ready for the unexpected. If they have too fixed an idea about what they are looking for, they may see that result even when it doesn't occur, or fail to see the new, odd thing that is happening off to one side. They may even stop an interesting investigation, thinking it has "failed" because it isn't producing the results they expect, just when they are on the verge of discovering something completely different.

The astronomers who discovered the background radiation that is used to support the theory of the Big Bang were doing a survey of the sky and thought that the pesky radio hum that messed up their observations was some problem with their instruments. If they had given up in frustration because things "weren't working", or factored out the hum as instrument erro, they would have missed one of the great astronomical discoveries of the twentieth century.

Not only do scientists have to be ready to adapt to different experimental situations, but they have to be aware that the different situations call for different reporting methods. Some reports must display trends in numeric measurements, results that require charts and graphs. Other reports must rely on long verbal descriptions because simple numerical measurements weren't possible.

Doing science in an educational framework has its own dangers. Because so much emphasis is placed on technique (which should produce measurements within certain error limits), too many students do science experiments with the idea that they are following a cookbook. If they have the right ingredients and follow the instructions properly, they will get the right product. An experiment fails when it doesn't produce the right product. It doesn't matter whether they understand what happened, or why, as long as they get the right answer.

I'd like to avoid that kind of lab work as much as possible. I've tried to design the labs for this class to help you learn to think like a scientist, and to do that, you have to learn some of the techniques that scientists use in creating and performing experiments. But beyond that, you will have to do some creative thinking from time to time, from following fairly explicit instructions to coming up with your own experiments from scratch.

With those caveats, let's look at what makes a good lab report, by looking at why we do science in the first place. One of the assumptions of this course is that the natural world is real, objective, and ordered, and that this layer of reality can, to some extent, be discovered through careful observation and accurately described. These conditions mean that the natural world exists outside of our experience of it, follows certain patterns of cause and effect, and is experienced similarly by different people. Our goal in writing a science report is to communicate our experience so that someone else will understand what we experienced and why we drew certain conclusions from that experience, and will have enough information to copy the experience for themselves and test whether or not the same things happen in the same conditions.

To accomplish this, your report must explain what you did and how you did it in enough detail that any similarly equipped person can repeat your procedure and collect the same type of data for comparison with yours. It must also explain how you did any calculations, so that others can perform the same calculations on their data, and see if they get the same results. Finally, it must clearly state your assumptions, analytical thinking, and conclusions, so that your peer scientists understand why you interpreted your results a certain way. They can then repeat your experiment, calculate their own results, and determine whether your conclusions are reasonable.

A common way (but not the only way!) to organize a lab report is as follows:

First, state your goals or hypothesis. Like the opening paragraph of a good essay, this explains to the report's readers what you want to do, and to some extent, the direction of your investigation.

    A goal is something like "To see what happens to a bucket of ice when I leave it in the sun." Here you have no stated expectations of the outcome, and you are ready for anything. (Strictly speaking, this isn't a controlled experiment but a directed observation. It is still a valid way of scientifically gathering information.)

    A hypothesis is a statement whose veracity (whether it is true or false) can be tested by the outcome of your experiment. An example would be "Ice melts more quickly in full sunlight than in shade on a hot day." Here you will have to get results from two sitatutions that you can compare, and yourexpect that your results will be something along the lines of "My experience shows that ice melts more quickly in direct sunlight." You could, however, find that ice melts less quickly ... which might lead you to check what the ice is made of, or whether its container reacts oddly to being heated, or whether your thermometer is working.

Next, explain what materials and equipment you used, and what procedure you followed. Remember that your goal in this part is to make it easy for people to understand what you did, and to repeat your experience if they like. Lay out your information in a convenient form: use lists for the equipment and materials, grouped together for each part of your experiment. Number the steps of your procedure so that they are easy to follow and the order for each activity is clear.

  • Materials:
  • Aluminum ice bucket
  • Thermometer with .1 deg accuracy from -10 degrees to +110 degrees Centigrade
  • Ice cubes (approx. 50 3cm cubed)

    Procedure:

  1. Make ice in refrigerator using standard size ice cubes. Freeze for 3 hours.
  2. Dump ice into aluminum bucket until bucket is full.
  3. Place ice bucket in direct sunlight.
  4. Note time and temperature inside and outside ice bucket.
  5. Allow ice to melt without interference (do not stir).
  6. Examine ice at 15 minute intervals until ice is mostly melted, then watch continuously until all ice melted.
  7. Note time and temperature inside and outside the bucket.

Record data. You will need to record your raw data carefully. This is the meat of your experiment, so think about how you will record and present data before you actually perform the procedures. You will want to consider possible sources of error, and record more information than you will actually put in the report. If the experiment involves calculations, you will want to do a few to see if the outcomes are within your expectations.You should give samples of any calculations that you do to get derived results from raw data; your reader should be able to do similar calculations with the rest of your data and get the same derived results.

    Raw data:

  • 10:03 Bucket temp: 1.05 Temp of air next to bucket: 38.3 (degrees Centigrade)
  • 10:18 Approximated 1 inch of water in bottom of bucket.
  • 10.33 Most of ice melted
  • 10:37 Ice entirely melted. Icewater temperature 1.7. Temp of air next to bucket: 36.3 (deg C)
  • Temperatures accurate to 0.1 deg. Measured air temp in same place.
  • Temperature change of ice to water: 1.7 - 1.05 = .65 deg C.
  • Temperature change of surrounding air: 38.3-36.3 = 2 deg C.
  • Elapsed time: 10:37 - 10:03 = 34 minutes

Display your results in an easy-to-understand format. You may need to record your data in one format because it is easy to do that during the actual experiment, but report it in another format so that your readers can follow your conclusions, especially if you make repeated readings of a given process. If you want to show exact data, use tables with columns arranged to make comparison of similar data easy. If you want to show trends (increasing or decreasing numbers as some factor changes), use graphs with lines or histograms (bar charts). If you want to show parts of the whole, use pie charts. The bottom line: chose the graphic form that best shows the relationships between your measurements.

It is both easy and apprpriate to use a spreadsheet such as Excel or Numbers to record data and generate calculations. You do need to report the formula used to generate the columns. You can save selected rows and columns as HTML to a text file and copy them directly to the Moodle assignment page as part of your report.

    Trial # Start Time Air Temp Ice Water Temp Water state End Time Air Temp Ice Water Temp Water State Air Temp Diff Water Temp Diff Elapsed Time
    1 Shade 10:03 38.3C 1.05C Mostly ice 10:37 36.3C 1.7C Water 2.0C 0.65C 34 minutes
    2 Sun 10:55 39.5C 1.05C Mostly ice 11:17 37.0C 2.5C Water 2.5C 1.45C 22 minutes
    3

List and explain your conclusions. Describe your results in general terms and the trends the data supports. If you had an open goal to start with, you may now want to make a hypothesis and suggest what changes you would make to the experimental procedure to test it. If you started with a hypothesis, you will need to explain whether it passed or failed your experimental test. You may still want to suggest further possibilities for research. If you got completely unexpected results, you will need to suggest sources for the actual results, either problems with your procedure, or natural forces that you did not originally take into account.

    While it would take many more iterations to conclude this, the two trials above clearly show that when the basin is placed in directly sunlight, the ice inside melts much more quickly than it will in the shade.

I hope this gives you a better idea on how to approach lab reports. A good resource for more information is The Art of Science, by Joseph Carr. It explains how to do scientific research at many different levels, from doing experiments for a science fair to doing original research as a graduate student or professional scientist.