Bernard Nebel
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Thank you for your question. It is not all silly. You have a valid point. I was thinking of air as “atmosphere”, which existed on Earth well before living things, and therefore, “natural earth”. To be sure, plants have altered the atmosphere by providing more oxygen, but oxygen is inorganic; it did exist before life although not in as large amounts. But another argument comes into the picture.
Your question has caused me to think about it more myself, and I believe that therein is the answer. A key reason for making and putting things into categories, as pointed out in the lesson, is to help us organize and pursue our thinking regarding a topic. Here, we are having kids look at the entire world and it serves their comprehension to separate it into the categories. Of course, nature “feels” no obligation to fit neatly into our human-conceived categories.
We begin to see aspects that don’t fit clearly into the categories we have created. From this point of view, it should go here; from that point of view it should go there. Maybe there should be another category. But, would we engage in such thinking at all if we had not created the categories in the first place? In short, one may take exception with certain aspects, but this is because the process has stimulated thinking, and thinking stimulates learning.
Please ask further questions.Thank you for catching this, Tom. It amazing things can slip by.
Thank you for your questions. The only major thing you need in addition to a compound microscope is a triple beam balance. Other things you will need can be picked up a local store as you need them. Sorry, I don’t have a complete materials list for Volume II. However, I think someone in the BFSU Facebook group made one. The BFSU Facebook group is at:
https://www.facebook.com/groups/308651699340117/permalink/1311845535687390/Hi Sherrie, thanks for writing.
Regarding “tips, encouiragement for someone who is starting at ground zero and has to teach”,
I suggest shifting your focus from “having to teach” to going on an exploration, learning adventure along with your kids. You need not be shy about saying that this is new to you too and perhaps they can help you (seriously) as well as you helping them. Keep in mind that teaching is not brain surgery. If/when you mess up you can alway go back and try it again. Bottom line: Have fun learning along with your kids. You will be a great role model in doing so.Regarding, “my daughter will be in grade 8/9 next year.How long would you suggest we spend on this book, since we would still need to complete book 3.”
First, I think finishing both books II and III in one year is an impossible goal. And, it is a goal that is unnecessary to reach. Where will your daughter be attending grades 8/9? If public school, it is most unlikely that they will expect any significant science background for introductory science courses. If continuing to homeschool, just keep plodding ahead as you are doing. Learning cannot be rushed; it will take as long as it takes.
I hope this helps, but please write again.
Sorry not to get back to you until now. From what you describe, I think the problem is in the way you are using your microscope. Use the condenser to cut the light way down so that the background is only a light gray. Then carefully focus. Be sure you are focusing on the liquid under the coverglass. Get a rough focus with 40x, then go to 100x. Hopefully, this will give you something similar to what you see in videos.
I am very happy to see that you are (attempting) giving your kid(s) a first hand experience of this. Please let us know how it goes from here.
Sorry Shelley, I don’t have any specific recommendations for beyond Volume III. There is huge number of possible pathways. My hope is that after completing the three volumes of BFSU kids will have developed an interest in what area(s) they wish to pursue further and there is a plethora of texts in each. My advice, then, is to go to Amazon, search texts in areas of interest, read reviews, and make choices accordingly.
Thank you for your question. Please let us know what you find, decide, and your future progress. I am sure that many in the group would like to hear. Best, and stay safe.
Yes, quite so. It will be interesting to observe how, over the period of the equinox, the noon shadow (what there is of it) will shift from north to south, or vis versa.
In the whole process, don’t let kids loose track of basic phenomenon–the shift is due to the Earth maintaining the same degree and direction of tilt as it orbits the sun.
You are quite right. A traditional sundial will not work at the equator. During the summer months (spring equinox to fall equinox) the arc of the sun’s path will go to the north of you making shadows fall to the south and the opposite during the winter months. However, you can still make a modified sundial. Mount a pole vertically in the ground (or straw vertically on poster board). Each day its shadow will start as long to the west, gradually shorten to zero when the sun is directly overhead at solar noon, then gradually lengthen to the west. You can calibrate the length of shadow with cross lines for each hour. These hour lines should remain consistent throughout the year, although the sun will proceed to make a low arc south and north of directly overhead.
This will not permit the determination of north as described in the text. However, a line from the tip of the first morning shadow to the tip of the last evening shadow will be an almost perfect east-west line. A perpendicular line, of course, will be north and south. Thanks for the question. Please ask further.
Thank you for your questions. They show good thinking.
Why can’t we “un-burn” a piece of wood?
Reese is quite right in his thinking. The formula for any chemical reaction can be written backwards as well as forwards, making it theoretically possible. Specifically the chemical reaction for burning wood (mostly cellulose) is:
C6H12O6 + 6O2 —–> 6H2O + 6CO2 + release of energy
The reverse (unburning) is:
6H2O + 6CO2 + input of energy —-> C6H12O6 + 6O2 and is theoretically possible. In fact, plants do this with the aid of light energy. It is called photosynthesis.
However, distinguish theoretical possibility from practical feasibility. Plants accomplish the unburning of wood (photosynthesis) through a dozen or more individual chemical steps driven by energy from light. To have it happen on one big step as occurs in the burning is what is impossible.Its a little like smashing a dinner plate on the floor. You can see the smashing apart occurs with one bang. You can see that the pieces might go back together to “unbreak” the plate. Then you might do so by carefully picking up each piece and fitting and glueing them back together. What remains impossible is having them go back together in one “bang.” Thus we say that the breaking of a plate (and unburning wood) are irreversible.
Is there conservation of mass as well as conservation of matter?
Yes! (But don’t confuse mass and weight.) Since each particle (atom) of matter has a certain mass and atoms remain the same, mass will also remain the same. Seeing this in practical way is what is difficult. Note from the above equation for burning wood, the major products are carbon dioxide and water (vapor) which go off in the air. (They retain their mass although weighing them is impractical.) A very small portion of the log ends up as ash. To prove that mass (in terms of weight) remains constant, you would have to burn the wood plus sufficient oxygen in a totally sealed container so that the water vapor and carbon dioxide are held in. (Scientists have done this.) It is found that the total mass and weight
does not change.Please question more as you wish.
This sounds fine. Plus, you illustrate an important aspect of learning. When you can take a concept and explain it your own words, it shows you have really mastered it. Nice work. However, I would make an adjustment to your line, ” The sensation of weightlessness does not mean you dont weigh anything at all.” This is where we should switch from speaking of weight to speaking of mass. That is, a scale will read different weights depending on gravity–zero in a state of free fall. But you and anything else remains constant. We speak of that “weight” that remains constant as mass and measure it in kilograms. That is, a mass of 10 kilograms will remain 10 kilograms regardless of any force of gravity including zero force.
Thank you for your question. Please ask further.
There is nothing like experimental data to get at the truth.
You have discovered an error in the text. The baking soda-vinegar reaction is endergonic. That is, heat from the environment is sufficient to drive the reaction. As heat from the environment goes into the reaction, the temperature falls.
Congratulations and thank you for exposing this error in the text.Sorry to harp on what you already know well, Cindy. I try to compose answers that speak to others in the group. I hope more will join in and comment or ask questions. I would love to see this group generate more questions and discussion.
Regarding your first question, everything human-made starts with from something biological (add) or NATURAL EARTH categories (or both). A tin can, for example is from natural earth materials–iron ore. (How much work sheet stuff you have your son do is up to you. If he enjoys it, fine; If he doesn’t like it, go easy on it. We don’t want him to get the feeling that science is too much forced dull work.
To round out the concept, introduce the word “resources”. Everything human-made demands starting with certain resources–biological and or natural earth.
Regarding your second question. I would let it go for the time being and move on to Lesson C-1. There you will develop concepts of energy and forms of energy, which are very different from any form of matter. Then you can come back to fire and the sun. What we witness here is heat and light, i.e., forms of energy.
The concept you are heading toward is that we have two things: matter (biological and natural earth) and energy, which makes everything go, work, or change. Energy becomes a required resource for everything we do/make in addition to the material resources.
Please don’t expect that learning should occur in specific steps that kids can check off on a worksheet. The vastness of everything out there is bound to cause confusion and missunderstandings. The real learning occurs as you recognize and accept the confusion and struggle with sorting it out and correcting the misunderstandings. You are on the right track by asking questions. Please keep at it.
Thank you for your question. I think your son (for age almost 5) is expressing remarkably good knowledge and understanding. A perfectly logical argument can be made for paper being biological as it is made from from trees. It is quite arbitrary that we move it into the human-made category to express the role that humans played in producing it. Recognizing that everything human-made starts with resources from biological and/or natural earth categories should be a major point of this lesson.
I don’t know if this helps. Please ask further as you like.
