20 October Science 8 Rivers

Today, acknowledging your up-coming trip to and on one of the greatest rivers in the world, we’ll discuss Rivers.

Check out the geography of our region. What do you notice? Why is Tibet considered a strategic region? How many watersheds begin in the Tibetan plateau? What percent of the world’s human population depends on water from these rivers? What are some potential consequences of climate change on the way the water cycle works in this region?

Start a folder in your DSN called earth cycles. Put your notes from today in that folder. We will begin Earth Cycles in January. So today is a preview and an introduction to things to notice and think about during WOW 8.

Mr. Friel told me this was near the 8th grade put-in point. I’ve never been on the trip so I don’t know for sure. I will have my sci 8 kids look at the aerial photo and try to trace the river down stream. Rapids are named on some of the areas when you zoom to a certain scale.

30.145721N  78.5980797E (coordinates–use with any map app or website)



Look at the put in point. Follow the river all the way to Rishikesh. Zoom in on the rapids, on the shore, on the surrounding hill sides.

  • How many tributaries can you find from the put in to Rishikesh?
  • Which way does the Ganges flow?
  • How many times does it change directions? (You can zoom in and zoom out to see the pattern at different scales.)
  • What other questions come to mind as you make a virtual river trip? An important thing to remember is that “water flows down hill.”
  • What else determines the path a river takes?
  • What signs of human impact on the river and the surroundings can you see?
  • In reference to rivers and their landscape, what do you think watershed, drainage basin, and catchment area mean?
  • Where do you think you will camp? (Take a screen shot. Crop and print. Take with you on the trip and see if you are close.)

Look at this

Killing the Ganges with Justin Rowlatt (AES parent)


Ecological and strategic importance of Tibetan Plateau: http://www.meltdownintibet.com/

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19 & 21 October Science 7 Preparation for WOW–Stream Science and River Walk

View and discuss Part 1 and Part 2 in WOW Science from a presentation for previous years:


  • How many kinds of living thing do you expect to observe during the WOW trip?
    • Viewing the landscape from the
    train and from the bus?
    • Walking around Camp Panther / staying at the Himalayan Bear Stream Camp?
    • Hiking to the school and waterfall and up the small river to the swimming “hole?”
    • Conducting the stream study / during the river walk activity?

Look at the maps and aerial photos. What do you notice? How will you orient yourself in the landscape when you are at WOW? Discuss some possibilities.

Look at the pictures of the aquatic macro-invertebrates could in the stream. What are some features to notice that will help you describe and distinguish them?

See this reference:

Pictures from past WOW trips:

See materials on aquatic macroinvertebrates: https://drive.google.com/a/aes.ac.in/file/d/0B4DPwlouN3dISGRlZ0pLZllGXzA/view?usp=sharing

Bugs of the underworld:

Watch the short video http://www.youtube.com/watch?v=KVMCPXDohgA

Notice from our pictures that we use a different style of kicknet and we return any organisms caught back to the stream.

View the presentation     The Art of Birding

Concentrate on becoming familiar with the “things to look for” the Seven S’s. The birds in the presentation are from North America so we will not see them in India. But being able to describe birds you see by using the Seven S’s is very important. Remember a well-described bird without a name is much better than a misnamed bird.


Practice using the binoculars.


1. Always use the neck strap around your neck. Never carry the binocular by the neck-strap.

2. Never touch the lenses. Never play with the eyepieces or focusing knob. Only use them as directed.

3. Spot a bird first, and then bring the binoculars to your eyes.

4. If you wear glasses, fold back the rubber eyecup so the binoculars will come closer to your glasses.

5. Do not drop the binoculars. When handling the binoculars, do not engage in activity that could lead to your dropping them.

6. To focus: Close your right eye and use the center focusing adjustment to get a clear image of something at least 15 meters away. Then close the left eye and adjust the right eyepiece to get the clearest image possible. You should not have to turn the eyepiece very far. If you do, alert the instructor. Use both eyes and spread the two parts of the binoculars until they match the distance between your eyes. You should see a circular field of view with a clearly focused image.

7. As a class, go outside and find a bird that is easy to observe (pigeon, common myna, jungle crow, jungle babbler, black kite, etc.). Practice using the binoculars and the Seven S’s. Work with a partner where one observes and describes and the other records. Then change roles.

8. When animal watching, only talk when necessary. Do not talk loudly. Do not make rapid dramatic movements. Do not scare away the animals you are trying to observe.

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18 October Science 8 Triangles, scaling, mapping and measuring, observation of the sun, measuring the height of things indirectly

Today goes into your astronomy folder.

We are doing astronomy now because of the equinox, the weekend full moon, your WOW 8 excursion where you will have the chance to see the sky for extended periods of time.

Check for the dates of WOW 8:

Indirect measurement: Using triangles and scale drawing to determine angles of elevation and heights (distances).

Refresher on triangles.

A universal sundial. Observe and explain how it works.

A vertical stick (gnomon).

Height of a tree.

Height of the building. (check with direct measurement)

Moon observations. What have you seen?

Can you explain this cartoon?


Mapping from The Ring of Truth https://www.youtube.com/watch?v=yRY2SkMTafc

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17 October Science 7 Newton’s 3rd Law, Momentum, Conservation of Momentum, Rocket Design and Experiment

Newton’s Laws of Motion

1st Law is a starting point, an assumption about mass and motion.

Anything that has mass tends to keep its velocity (constant speed in a straight line). Anything that has mass tends to resist changing its velocity. This is taken as a property of mass. Newton did not know why this is the case, but he was able to discern the pattern.

2nd Law is about what is necessary for a mass to change its velocity. The cause of any change in speed and/or direction is called a force. The force is proportional to the size of the mass and the rate of change of velocity. The 2nd Law is often written F = ma. This form allows calculations and predictions about the size of forces and the relation to mass and the rate of change of velocity (acceleration).

3rd Law establishes symmetry. Every force gives rise to a second force, equal in size but opposite in direction.

(Many students are misled when the third law is expressed: For every “action” there is an equal and opposite “reaction.” This may be because people include far more things in the idea of what action and reaction mean. It is best to stick to “force.”)

We will do a brief experiment / demonstration with the 3rd Law. Then we will introduce a new quantity: Momentum.

Momentum can be measured. It is mass x velocity or mv . Remember velocity is speed with the direction of motion specified. This velocity is instantaneous–see our last class.

You could think that the 1st Law is about momentum being constant and the second law is about momentum changing. This is one of the great cross-cutting concepts in science–what stays the same and what changes.

Momentum can be transferred. The total momentum of a system is conserved. This suggests how deeply the property of inertia is ingrained in the material world. The symmetry of the 3rd law is definitely related to this Conservation of Momentum and this fact that momentum can be transferred. The Law of Conservation of Momentum is important in describing how rockets work.

Newton’s view of motion is a beautiful mental structure that accounts for much that is observed about motion in the world and beyond. Later Einstein (and others) saw some inadequacies and developed a new and more comprehensive structure to explain and predict (such a structure is called a scientific theory). Nevertheless, Newton’s scheme is still taught (see us!) and used (pilots and air traffic control are vivid examples) today–hundreds of years after Newton.

Pick a partner, discuss your own theories of how a rocket launches and flies. Include both sketches and words. Be prepared to share. Design a rocket–drawing and words–that you could make from the plastic bottles. Plan a simple experiment you could try (everyone will be guaranteed 2 launch attempts). Explain the rationale of your experiment and what you think will happen. Be sure to include how you will make the observations. Discuss what you are trying to test.

See the Bill Nye episode on Momentum.


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14 October Science 8 Catching up–How to determine a complete reaction

Several things to do today:

  1. Clean up bottle experiments. You may test the gas as demonstrated 2 classes ago. Conditions: Only one basin and one test at one table at a time. When you are ready to test, call me (Dr. F) to your table and explain the planned procedure. Remember all safety precautions.
  2. If you do not want to test the gases, just clean up the bottles. Take off the tape label.  Empty the contents–liquid down the sink; solids in the dust bin. No solid material in the sink, please. Rinse the bottles and place them in the box upside down. Put the lids in the designated container.
  3. If you have not done so, enter your data in the spreadsheet for the mass of the vinegar and baking soda reaction in a closed container. https://docs.google.com/a/aes.ac.in/spreadsheets/d/1hWjsbOp17SJ8QmKZPCLgmAi789UvalbGIkjqqo2FNXI/edit?usp=sharing
  4. Today / Tonight view the moon. Check out the view for 14 October: https://www.timeanddate.com/moon/india/new-delhi

Begin keeping a moon journal. Make a sub-folder in  your astronomy folder. For each observation:

  • date
  • time
  • location (describe as precisely as you can
  • direction you are looking along the horizon (bearing or azimuth)
  • angle of elevation above the horizon
  • appearance–phase, orientation (photo if you have a good camera, sketch; if you have binoculars, look at the moon and notice the appearance of the surface; it is very interesting to look right at the edge of the illuminated portion; what do you see?)

5. Be sure you have answered the homework questions:


  • What does the author mean, “we all practice chemistry without being aware of it?” Please include specific examples to support your answer. Refer to a paper from the beginning of our unit Fundamental-questions-about-matter.
  • What part did craft knowledge play in the development of chemistry, according to the author? Use specific examples.
  • What were the dreams of “alchemy?”
  • What are some of the “ironies” in the history of chemistry? Look at the stories of various substances to see where they started and the surprising place they ended.
  • What is meant by “tapirage?” Why is this example included in the article?
  • What is the role of the balloon in the development of chemistry? What is significant about a balloon in studying matter?
  • How did ideas about elements change from those of the ancient Greeks to those of scientists who followed Mendeleev?
  • Pick one of the pictures and write a detailed analysis of it.

6. Bring your observations–evidence/argument–atomic-molecular theory chart up-to-date. Show me (Dr. F). Matter chart (this should be updated with each matter experiment and activity matter-chart or


7. In a new group of 3. Discuss how you would address this question/problem: What is the proportion of vinegar and baking soda that will completely react with each other so that no vinegar is left over and no baking soda is left over. What can you do to see that neither of the reacts remains after a reaction? Remember that in a chemical reaction, the molecules of the reactants are rearranged to make new molecules. (The total number of atoms remains unchanged.) If the reaction is complete, there are no more of the original molecules. When you have an idea, discuss with me (Dr. F.). If you have 5 grams of baking soda, how much vinegar is needed so that all the 5 grams of baking soda reacts and all of the acetic acid in the vinegar reacts? That means there is no more baking soda and no more vinegar. How much gas (in grams) is produced from these portions?

8. Bring your digital science notebook up-to-date.

  • An entry for every class. Each entry includes:
  • Notes you would normally take.
  • Sentences about what you did
  • Sentences about what you saw
  • Sentences about what you and others talked about
  • Sentences about your ideas, questions, wonderings, reflections
  • A photo of something important from the class that helps you think and remember
  • A sketch of something important from the class that helps you think and remember–the sketch can be of an idea, it does not have to be of an object.

Show and tell of DSN soon.


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13 October Science 7 Acceleration due to gravity, a word about instantaneous velocity, momentum, and more



Find these average speeds:




Conservation of Momentum Demonstration

Air-pressure water-rockets

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12 October Science 8 Chemical reactions continued

Today / Tonight view the moon.

Here is the data:

The moon rises in the eastern part of the horizon this afternoon at 15:21. It will cross the north-south line in the sky, called the local meridian, at 21:08. It will set tomorrow morning at 3:00. The illuminated part of the moon is getting larger and brighter. It rises later each day, crosses the meridian later each day, and sets later each day (be sure to observe this in addition to seeing the times on the linked chart below). The moon will be full on the 16th. It rises at sunset, sets at sunrise, and crosses the meridian close to midnight. Why would this be?

Begin keeping a moon journal. Make a sub-folder in  your astronomy folder. For each observation:

  1. date
  2. time
  3. location (describe as precisely as you can
  4. direction you are looking along the horizon (bearing or azimuth)
  5. angle of elevation above the horizon
  6. appearance–phase, orientation (photo if you have a good camera, sketch; if you have binoculars, look at the moon and notice the appearance of the surface; it is very interesting to look right at the edge of the illuminated portion; what do you see?)


Today we will carry out the vinegar and baking soda reaction in a closed bottle.

You should have some idea about the results. Be sure to write down your expectations.

Enter your data on the class spreadsheet:


Use 4 grams of baking soda and 50 grams of vinegar. (See the amount of gas evolved in the open bottle experiment from a previous class.)

See the following photos and observe the demonstration in class. This experiment demands careful technique. Listen to the details. Ask questions.









The vinegar has been poured into the bottle. The baking soda is wrapped loosely in a bundle of tissue (not paper towel). A corner of the tissue is held by the tightly closed cap so that the bundle is NOT in contact with the vinegar. It is VERY IMPORTANT that the tissue does NOT extend outside the cap. If the tissue does extend outside the cap, your system will not be completely closed and both gas and liquid can escape. When you have set up the bottle properly, you can find the mass of the entire system. Compare this technique to the box of changes we saw in the Ring of Truth video segment on the Conservation of Mass during last class.









In this picture the bottle has been tilted so that the vinegar wets the paper while the bottle remains tightly closed. Compare the scale reading in both pictures.









In this picture, the cap has been loosened and then removed after the gas escapes. It is important that only gas leaves the bottle. Small drops of liquid that escape will make the loss of mass look larger than the mass of the escaped gas.

Vinegar is 5% acetic acid in 95% water. Acetic acid = CH3COOH. The chemical name of baking soda is sodium hydrogen carbonate. The formula of baking soda = NaHCO₃. What do you think the products of the reaction are? Why? What do you think the gas is? What is the source of the gas–the acetic acid, the baking soda, or both? What is your reasoning? What would molecular models of the reactants look like?

*  * * * * * * * * *

You may take apart the bottles from the previous experiments.

  1. Do not discard any of the non-liquid materials in the sink. Use the dust bin. Remove tape labels from bottles and rinse bottles.
  2. If you want to test the gases, check with Dr. F, after you have everything set up. One basin for 2 groups. One gas tested at a time. Everyone has safety glasses. You need to be able to describe the procedure step by step to Dr. F.
  3. Classroom must be clean and straight 5 minutes before dismissal time.

Be sure to have a complete digital science notebook entry for today.

  1. Regular notes.
  2. What we did (do not need to describe clean-up, just the experimental procedures conducted)
  3. What you saw. All results, data, observations.
  4. What you talked about–introduction, closing, conversations with partner about the experiment, conversations with Dr.F.
  5. What you think, wonder, expect? Your reflections.
  6. Photos of important aspects of the class.
  7. Sketch–not necessarily of objects. Could be of ideas. (Perhaps your first imagined structures of the acetic acid, baking soda, gas, other product(s) molecules.)

Homework due in DSN next class:


What does the author mean, “we all practice chemistry without being aware of it?” Please include specific examples to support your answer. Refer to a paper from the beginning of our unit Fundamental Questions about Matter.

What part did craft knowledge play in the development of chemistry, according to the author? Use specific examples.

What were the dreams of “alchemy?”

What are some of the “ironies” in the history of chemistry? Look at the stories of various substances to see where they started and the surprising place they ended.

What is meant by “tapirage?” Why is this example included in the article?

What is the role of the balloon in the development of chemistry? What is significant about a balloon in studying matter?

How did ideas about elements change from those of the ancient Greeks to those of scientists who followed Mendeleev?

Pick one of the pictures and write a detailed analysis of it.


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10 October Science 7 Free fall and partner tree

Today we will try to gather data on the free fall of a lump of clay from the outer stairs. We will need full cooperation of the class–good observations–timers and videographers, complete recording of the data, full attention. Safety is paramount.

We will distill the time data using medians of the timers (5), and medians of the trials. We will graph the heights (distances) from where the clay ball is dropped and these median times for the descent.

We will see what our graph looks like and discuss what the ideas of Galileo and Newton predict.

If we get “nice” data, I will show those interested a graphical technique for determining instantaneous speeds. With instantaneous speeds it is possible to determine the rate of acceleration. (Acceleration cannot be determined with averages speeds. Average speeds, however, can give you a sense that the speed is changing.) Data from all classes will be made available for comparison purposes.

Before we begin, make sure you have drawn an expectation sketch graph. Explain your thinking.

Why is gravity considered a force?

When Newton was asked what gravity “is,” he responded, “Hypotheses non fingo.” (Latin for “I feign no hypotheses,” “I frame no hypotheses,” or “I contrive no hypotheses”–from the Wikipedia entry.) What do you think he meant?

Gravity is an example of a force that acts across a distance with no visible material connection between attracted objects (there is no “string” between the earth and the moon, for example). What ideas can you imagine that would explain the way two objects can be attracted to each other without being connected by something material? (This is one of the things that bothered Einstein, who developed a physics of motion based on different assumptions about space and time from Newton. Einstein’s system can incorporate Newton’s ideas as well as more general predictions from the very large, the very small, and the very fast. If you are interested in Einstein’s ideas, see me and I can recommend some resources.

Period 8 (median of the median times for each height):

  • 9.0 m — 1.16 sec
  • 8.5 m — 1.07 sec
  • 5.3 m — .85 sec
  • 4.6 m – .75 sec
  • 2.3 m .48 sec

Period 8 clay ball drop from outer stairs


Of interest:





Partner Tree.

Visit your partner tree today. Observe something new from your first visit. Observe any changes. Record your observations. Organize a folder in the GDR folder for all your partner tree observations. Find out more through research about your species. Prepare for WOW by increasing your awareness of the “nature” around you. Open your eyes and mind to “noticing” and “looking.” See things you’ve never seen before, never thought about before. As the Japanese haiku poet said, “Learn about pines from the pine, and about bamboo from the bamboo.”

See the following tips for observing trees:

tree1 tree2 tree3 tree4 tree5 tree6 tree7

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4 October Science 7 Motion, Inertia, Force, Acceleration–Newton’s Laws

Read, Explain, Question, Summarize and Reflect

Newton’s 1st Law of Motion

is about a property of matter called inertia. If you realize that the cart could keep moving in a straight line with constant speed with no one pushing or pulling it (see graph below), you have understood a great deal about the concept of inertia. If you realize why it is important to wear a seatbelt in a car or airplane (or any moving vehicle), you have understood a great deal about the concept of inertia. Newton’s First Law of Motion is stated in several different ways. I suggest you examine some of these different ways and think about what they mean and how this law establishes a starting point for describing and understanding motion. You might find treatments like this <https://web.phys.ksu.edu/fascination/chapter7.pdf> useful.

Find as many different ways that people state Newton’s First Law of Motion as you can. Write a conclusion of your own.

Think about the times when an airplane pilot turns off the seat belt sign. Those are the times when an airplane is moving at a constant speed and is not changing directions. During those times you are in an inertial frame of reference. That means you can do any experiments with motion and you will get the same results you would if the plane were sitting still on the ground! Understanding what frame of reference means is fascinating and fun.

Watch these classic films and see if you can figure out what is happening: <https://www.youtube.com/watch?v=aRDOqiqBUQY>. What does this mean, “All motion is relative?”

Galileo, the important and famous Italian scientist, died the year Newton was born. Galileo’s work on relative motion and on acceleration set the stage for Newton to derive his incredible system for describing and explaining motion. Newton’s is the system we are examining in Science 7. (Later you will learn about how Newton’s system is incorporated in a more comprehensive system of describing and explaining motion developed by the famous modern scientist, Albert Einstein).

Try this short animation <https://www.youtube.com/watch?v=uJ8l4kh_jto>.



















What happens when an unbalanced force is applied to an object? We first looked at this situation with the cart when we pulled it with a constant force. The cart changed its speed. You could think of how each successive instant of force was like a kick that ADDED to the existing inertial motion, thus the speed picked up. This link between force and acceleration is what Newton described in his Second Law of Motion. This law is often expressed as F = ma. What this expression means is that if a force of a particular size (magnitude) is applied to a mass, an acceleration occurs of a certain size. If the size of the force increases on the same mass, the acceleration increases proportionally. If a bigger mass is to be accelerated at the same rate as the smaller mass, a proportionally greater forces is needed to be applied to the greater mass.

Of great importance is the fact that mass determined by inertia (through the F = ma relationship) is equivalent to mass determined by acceleration due to gravity (Fgravity = mg (the rate of acceleration due to gravity).

This equivalence is important in resolving the puzzle of why two objects of different mass dropped from the same height at the same time reach the ground at the same time. See if you can use the concepts of inertia and gravitational force to explain the results of this puzzle that confounds many people.

How can we determine the value of acceleration?

  • Acceleration = change in speed / change in time
  • remember that speed is change in distance / change in time
  • thus acceleration could be expressed as change in distance / change in time / change in time
  • acceleration is the rate of a rate!!!

Before we have used the idea of average speed = change in position/change in time.

  • We need new concepts to think about changing speed or acceleration
  • Instantaneous speed and Instantaneous velocity. (Velocity is a speed with the direction of movement indicated)
  • Changing velocity includes speeding up, slowing down, changing directions. All of these situations are considered acceleration
  • To find acceleration we would need to know instantaneous velocities (how might this be done?)

We will see how this is important in a few upcoming examples.

Let’s try to get some times for a lump of clay falling from different heights.

We’ll do a few trials for each height and take the median times. Then we’ll find the average speeds for each height using the median times. We’ll plot a distance vs. graph using mean times.

We will needed everyone’s cooperation in timing, videoing, measuring, retrieving the clay, etc.

If anyone has a video app that includes a running timer in the background, please let us know. We can use the building as a kind of ruler.

See the video captures from another year. Let’s get better images and video this year!






Inertia refers both to constant speed and straight line motion. When both speed and direction are specified, the term is velocity. If speed and direction are constant, the velocity is constant. If the velocity changes, there must be a force.

Why is gravity considered a force? How do you think Newton related the fall of an apple to the orbit of the moon?

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3 October–Return Reports, Data on bottle experiments, STP conference prep, conservation of mass videos

Find the mass of the following bottles.

  • Vinegar and steel wool.
  • Steel wool and moist air.
  • Moistened paper towel and mung beans.

Enter data on the class spreadsheet. You need two “after masses” for the vinegar and steel wool; steel wool and air; and mung beans. Will mark data collection as formative assessment.


Do not open the bottles. Record any observations of the bottles themselves and the contents. Think about what might be happening.

If you did not set up the experiment, do so. You may need to restart an experiment. If the paper towel looks dry and your beans have not sprouted, set this experiment up again. You need enough water–but not too much.


Open powerschool and read the comments on your Mixing Ethanol and Water Report. You now have 2 weeks if you want to resubmit. In order to resubmit, you should read the comments and compare to your self-assessment. Ask any questions you have. Revise according to the comments. Resubmit with a copy of the comments, the original paper, and the revised paper, and a new self-assessment that considers the first self-assessment and what you have done in the revision. All of these documents should also be loaded properly in the digital science notebook. Due in two weeks if you want to resubmit.

Prepare for Student Teacher Parent conferences:

  • Create a document to hold links to various artifacts. Do not create a presentation or create a script. We only want you to have quick access.
  • Have your digital science notebook up-to-date.
  • Describe what you have found the most interesting so far this year.
  • Have examples picked out (linked) from your digital science notebook.
  • Pick out the most complete entry.
  • Pick out the entry where you feel you learned the most.
  • Pick out the entry where you were surprised, puzzled, or uncertain.
  • Have these three entries available for quick access (save the links an put them in a Student-Parent-Teacher document).
  • Pick out your most thoughtful blog post and have the link ready for easy access.
  • Be prepared to explain why you think it is most thoughtful.
  • Have your ethanol and water available with a link.
  • Have a copy of your self-assessment ready.
  • Have a copy of the power school comments ready.
  • Be prepared to discuss your revisions.
  • Your chart of observations of matter–linking evidence–behavior and structure of atoms and molecules (see: http://rfrazier.msblogs.aes.ac.in/2016/09/01/3246/ and http://rfrazier.msblogs.aes.ac.in/2016/08/28/29-august-science-8/
  • What have been the greatest challenges.
  • Why do you think they are challenging?
  • Be prepared to share a plan for how you hope to work in science for the rest of the year.

Link to data spreadsheets. Let me know when you are ready and I will give you editing privileges. https://drive.google.com/drive/folders/0B4DPwlouN3dIRmJyTE9zd2t3M3M?usp=sharing

See these two episodes from The Ring of Truth: An Inquiry into How We Know What We Know (Change)



Full Chapter Change: https://www.youtube.com/watch?v=Nk8CQNThbc0

Matter chart (this should be updated with each matter experiment and activity) matter-chart or https://docs.google.com/a/aes.ac.in/document/d/14unV7LBpxmPKBq8e0FXcNV9zEfgClQqJxUEKj-ODj5Y/edit?usp=sharing

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