What do you think was the motivation for writing this piece?

(Click the post title to read the submission.)

Hi Me’ira!

You may have realized by now that the site generates a random question for people interested in discussing your piece to answer.  Well, you clearly enjoy writing explanations, and I’d assume that’s the motivation.  However, I wanted to make a few suggestions…

1. Use accurate numbers, and if you want to use fewer digits, just say so.  For example, one inch is 2.54 cm, and 2.5 is close enough and easy to work with since 2.5 x 4 is 10.
2. Just to add to your explanatory writing, we can multiply any number by one without changing it, and this is the basis of the equations you provided.  It would be cool to see this pointed out.  A football field’s length can be multiplied by ONE so that it doesn’t change, but it allows us to change the units.  So, to change from 100 yards to meters, we multiply the 100 yards by a fraction equal to one that has yards in the denominator: 100 yards * (0.9144 meters ÷ (“per”) 1 yard).  One of the neat things I liked about physics was units analysis.  In this case, the yards in “100 yards” cross cancels with the yards in “0.9144 meters ÷ (per) yard” and we’re left with 91.44 meters.

Dave.

Dear Dave,
First of all, THANK YOU! I love getting ideas to improve my writing, and I’ll be working on your comments tonight!

<<<You may have realized by now that the site generates a random question for people interested in discussing your piece to answer.>>>

Actually, I didn’t realize that until I submitted this comment and saw the question at the top of the new page (yes, I came back in here and edited this comment. =) )

<<<Well, you clearly enjoy writing explanations>>>

Yeh, that would be the Master’s in Education =)

<<<I’d assume that’s the motivation.>>>

Actually, I’m working on this so my students might be able to get at least a little help at home.  Should I explain that at the beginning of topic 1?  Or perhaps as as precursor?  This is a fairly new guide that I’m writing, not too far past the first several topics.  I was hired to write a Hebrew school-wide curriculum, and apparently I"m doing quite well, so I thought I’d give this a try.  It’s not the same thing… a step beyond to push myself.

<<< However, I wanted to make a few suggestions…>>>

I have no clue if I’m doing this with any competence, which is one of the reasons I was so happy to find this place!

<<<, but it allows us to change the units.  So, to change from 100 yards to meters, we multiply the 100 yards by a fraction equal to one that has yards in the denominator: 100 yards * (0.9144 meters ÷ (“per”) 1 yard).  One of the neat things I liked about physics was units analysis.  In this case, the yards in “100 yards” cross cancels with the yards in “0.9144 meters ÷ (per) yard” and we’re left with 91.44 meters.>>>

I actually have dimensional analysis in topic 3 of this anthology!  You might be surprised how very quickly you can lose the attention of parents. One tiny topic at a time, or they’re gone and everything you’ve presented to them is tossed in a pile somewhere, or worse yet, in the circular file. 

<<<Just to add to your explanatory writing, we can multiply any number by one without changing it, and this is the basis of the equations you provided.  It would be cool to see this pointed out.  A football field’s length can be multiplied by ONE so that it doesn’t change>>>

Do you think I need to add to this explanation before I do the DimAn?

<<Use accurate numbers, and if you want to use fewer digits, just say so.  For example, one inch is 2.54 cm, and 2.5 is close enough and easy to work with since 2.5 x 4 is 10.>>

See above. The topic of Significant Digits (or “SigFigs” as we called them in my undergrad and grad math and physics programs) is discussed in a later topic, based on this lesson, so they can look back and connect it and have an Ah Ha moment. 

Thank you again Dave!
Me’ira

<<<Should I explain that at the beginning of topic 1?  Or perhaps as as precursor?>>>
Probably.  You know your audience better than I do.  The beginning of any presentation should be designed to attract the audience’s attention and give them some kind of handle to what hasn’t yet been presented yet so they can hang on to it and pull it toward them.

<<<I have no clue if I’m doing this with any competence>>>
There’s a thing called “imposter syndrome.”  You might like to explore how common it is and how we get around it.

<<<You might be surprised how You might be surprised how very quickly you can lose the attention of parents very quickly you can lose the attention of parents.>>>
Not just parents.  I am sensitive (some might say “oversensitive”) to the potential for confusion.  Confusion can come from too many pieces, but it can also come from poor organization.  You’re building comprehension and in the case of DimAn, the foundational piece is the fact that one is unity; we can multiply or divide by it as much as we need without really changing anything.  With DimAn, what we’re changing is our “numeraire” for the measure - the unit we use to give the number meaning.  Because that idea (multiplying or dividing by one only changes our view) is foundational, I’d start out with it.

The caveat is that traditional schooling doesn’t aim for building comprehension. There’s a guy named Brett Veinotte who has a podcast about the difference between school and education.  You won’t like the name, but I guarantee you’ll like the content.  It’s at https://schoolsucksproject.com/

<<<or they’re gone and everything you’ve presented to them is tossed in a pile somewhere>>>
I think that happens no matter what we do, except it’s never everything.  We remember the feelings we got best.  Use your audience’s love for their kids and I think you’ll find that the complexity of what you can present and still have a positive lasting effect will be very very high.  Another way to see this is that if you use baby food (“tiny topic”), it’s easy to get it into even the most resistant person’s gut.  If you instead make the food delicious and attractive, you won’t have to do much to get it in there.

<<<Do you think I need to add to this explanation before I do the DimAn?>>>
I do, but when I learned it, it was part of DimAn.  I think that’s because the professor teaching it felt, as I do, that things should make sense up front.  The alternative is that we learn a bunch of facts and behaviors that produce the right outcome.  Comprehension is paramount.  For example, here’s an important part of me: http://voluntaryist.com/how-i-became-a-voluntaryist/seeking-consistency-how-i-arrived-at-voluntaryism-by-dave-scotese/

<<<so they can look back and connect it and have an Ah Ha moment.>>>
I LOVE Aha moments.  However, when you first say “An inch is 2.5 cm” and then later say “SigFigs mean that even though an inch is actually 2.54 cm, we can say it’s 2.5 cm.,” you’re taking some risks that I don’t think are worth the Ahas.  Someone who knows 2.54 might think you’re sloppy.  Someone who puts a lot of value on accuracy will feel cheated (either at the beginning if they know it’s 2.54, or at the end if they only find out then).  Most people, in fact, are already okay with rounding, which is an unrefined application of SigFigs.  If you let go of your desire to create Ahas, you might find it easier to engage students (and parents).  “An inch is 2.54 cm, but we’ll round to 2.5 and address the difference in a future email (class, presentation, whatever). ...” gives them that handle I mentioned and shows that you know what you’re talking about.  OH OH Oh!  I have it.  Something to express this which I think has wide application:

Natural epiphanies are far more valuable than engineered ones.

In fact, given your interest in education and your happiness at finding my site, Brett might want to interview you for his show.  He’s always looking for people working in the field of education to interview.

Wow.  Thank you for so much constructive ... I don’t want to call it criticism because it wasn’t… maybe teaching? recommending?  And thank you for the shy honor of Brett. If that was to happen, what are the logistics of what would happen?

I don’t know the logistics so you’d have to ask him.  If you agree, I can let him know you’re interested in being (or willing to be - you choose the wording) interviewed and send him your email address which I already have.

I’d want to know more about it before I said yes.  That sounds like it would be self-esteem boosting which I could always use!

And thank you for your comments!!! I’m working on them and will resubmit when I get topic 1 rewritten!!

Rewrite:  A Parent’s Survival Guide To Physics by Me’ira Pitkapaasi page 1
          Topic One: Measuring Length Part 1: Inches, feet, yards, centimeters, meters

Measurement in Physics is not quite as simple as taking out your measuring tape.  This tool will come in handy occasionally, such as when you’re determining lengths that are large enough to see and short enough to personally reach.  On our measuring tape, that would be 1/8th of an inch to a yard; or a millimeter to a meter.  In the greater scientific community, we use the metric system, so in order to understand what your student is learning, we’re going to figure out how this system works!  An inch is typically the smallest unit of length used by the average parent in the U.S.A., or a fraction thereof.  We were always taught that an inch is about two and a half centimeters, which was correct! 

1 in (inch) = 2 ½ cm (centimeters)
or, more accurately,   
1 in = 2.54 cm

So how do we compute length from there?  We use a formula that you can understand if you can compute multiplication and division problems with your calculator, and you use the above equivalencies.
_____ centimeters = (2.54 centimeters) x (however many inches you just measured) ÷ (1 inch)
    Or
______ = 2.5 x (measured number) ÷ 1
    Or
If you’re measuring length of a standard piece of copy paper, you’re going to find that it’s 11 inches long.
________ = 2.54 x 11 ÷ 1 ________ = 27.94 cm

The length of your 11 in paper is also 27.94 cm.  Pretty cool, eh?

What if we’re measuring feet though? There are 30.48 centimeters in a foot. The formula changing feet to cm is very similar to the formula above:
      ______ centimeters = (30.48 centimeters) x (however many feet you just measured) ÷ (1 foot)
______ = 30.5 x (measured number of feet) ÷ 1

If you measured how tall your living room is, you might have discovered it was 7 feet tall.  Let’s put it into our equation:
______ = 30.48 x (7) ÷ 1   _______= 213.36 centimeters.

The height of your living room is 213.36 cm!  213.36 cm is an awkward measurement.  It’s quite inconvenient to measure the height of your living room by a couple of hundred units.  We use this equivalency: 

100 centimeters = 1 meter

With this equivalency we create a new formula:

      _______ m (meters) = (how ever many cm you are using) ÷ 100 cm x 1 m

Using our above measurement of the height of your living room,

      _______ m = (213.36 cm) ÷ 100 cm x 1 m
      _______ m = 2.1336 ÷ 1   ________ = 2.1336 m

A couple of meters tall is a lot easier to measure than a couple of hundred centimeters.

New formulas for longer measurements!  How about a football field?

Football fields are a bit long for your tape measure, but we know they’re 100 yards long.  Knowing that 214 centimeters as the height of your living room is a bit too high of a number to use conveniently certainly tells us that centimeters is not an appropriate measurement for a football field.  That’s check just to make sure, knowing that 1 yd (yard) = 91.44 cm.

      _______ cm = (how many yards you have measured) ) x 91.44 cm ÷ 1 yd (yards)
      _______ cm = 100 yards x 91.44 cm ÷ 1 yd
      _______ cm = 100 x 91.44 ÷ 1   ______ = 9,144 cm

This certainly shows that measuring a football field in centimeters isn’t the greatest method of measurement.  Who wants to count out nine thousand centimeters?  Let’s move on to the meter.  Just as we were often told an inch is around 2 ½ centimeters, we were often told that a meter was “a little more than a yard.”  Once again, fairly accurate. One meter = 1.09 yards.  So how do we find the length of a football field? 

______ meters = (1 meter) x (number of yards measured) ÷ (1.09 yards)
______ meters = 1 x (number of yards measured) ÷ 1.09
______ meters = 1 x 100 ÷ 1.09   _______ = 109 meters

Were you wondering where all of these formulas came from?  Equivalencies and Cross Multiplication are the two methods used to create these and many other Physics formulas.  Topic Two will cover these two methods.

Next passage: Topic 2: Equivalencies and Cross Multiplication

I read you voluntaryism piece.

Fascinating topic. I need to follow your links and read these books, thank you. I disagree strongly, however, that we should ignore the law and simply do what we want to do. That sounds alarmingly like Libertarianism which scares me to the core. The idea that people should feel free to steal from the grocery store, shoot trespassers ho are doing no harm to their persons, or abuse their children under the guise of parental right to discipline…. in my vie this just can’t be right. Society has to be able to decide as a whole the difference between right and wrong - at least to a degree. And to be able to line up appropriate punishments for these crimes. Your words before this last paragraph really hit home, and I look forward to reading more about them.