08-OCT-2012: Physics

Knowledge and Information...

My grandfather was a teacher. I don't mean that was his occupation, but that was the only real way to describe him in retrospect. And that is exactly how my father described him in his eulogy, and while few had imagined that's what he was before, everyone knew that's what he was afterward.

My father is also a teacher, and I also hope to honor them both by simply being able to live up to their legacy. I certainly try. I think that I would make an awesome formal physics teacher... for about one day, anyway. One day in particular: The first day.

The first day of a physics class, at least at this point in our societies' development, should really be about two things:

  1. Knowledge
  2. Submarines

Now settle in class, it's going to be a long session.

Can anyone tell me the difference between information and knowledge ? Anyone ? No one ? Okay, fine I'll just call on someone... Yes, you Timmy, go and get a dictionary and read to me the definitions of the words then.

Interesting definitions, wouldn't you say Timmy ? So can you tell me the difference ? Yes. Exactly ! The difference is, as you so elegantly put it, the difference between knowing something and having learned about something.

An interesting contrast, given that we are where we are. In a school, built for the purpose of you learning. Are we just here to shovel information into you ? No, of course not -- that would be ridiculous. We're here not simply to transfer information, but to impart knowledge. And so we arrive back at the crux of the matter ? What is exactly the difference between knowledge and information ? Well, it's as you may have guessed by now something more fundamental than either of them: Understanding.

Given that we may only give you information, how does understanding occur, and how does it lead to knowledge ? Well, with a bit of luck the information can be represented in such a way that you are able to decipher it. Once you are able to decipher it comes the hard part: You have to think.

I know, some of you probably think that you already think. Some of you may even suspect that you are doing so right now ! Perhaps. Do you all know at least KNOW what the difference between information and knowledge is now ? No ?

Oh well, moving on to the second part of today's lesson: Submarines.

Okay everyone, please design a submarine. You have 20 minutes.

I'll wait.

Done ? No ? Why not ? Too hard ?

No, not really. You just haven't thought about the problem. No, I'm not asking you to build a fancy ship, just a basic device which can be controlled to be operated underwater or on top of the water. The essence of the problem, therefore is how do you make a device float, then not float, and then float again ? Look at that, I've used understanding to make life simpler.

To build something like that, we must first know why some things float and some things sink.

So does anyone know why some things float and some things sink ? No ?

Any ideas ? Okay, Jane, there's an idea "weight" maybe heavier objects sink and lighter objects float. We'll call this our hypothesis for now.

Let's see if we can design an experiment that will give us the information we need to understand this.

Okay, let's get some supplies:

  1. A glass of water
  2. A ping-pong ball
  3. A golf ball
  4. A small ball bearing which weighs the same as the ping-pong ball

Alright, so we have our glass of water and our ping-pong ball. Let's see what it does. Well, would you look at that... it floats. Interesting bit of information we have here.

Next, we'll try our golf ball. It's heavier than then ping-pong ball, so it should sink according to our hypothesis. And wouldn't you know it, it does !

So are we correct ? Is it about weight ? Well, we don't know. All we know is one sank while the other floated. Let's try this other smaller ball, which weighs the same as the ping-pong ball. According to the prevailing theory it should float.

Hmm, how sad. It sank. It looks like we are idiots. Or we have cleverly discovered that our hypothesis is wrong through experimentation. Let's go with the latter one, it sounds better on our resumes.

Well, now we do have a problem. We have more information than when we started, but have not explained why some things sink and some things float. In some tests it appears to have something to do with with weight, while in other tests it appears to have something to do with size. What to do.

What's that Jane ? Why not both ? Brilliant ! It does appear that BOTH size and weight have something to do with the issue.

Let's call it volume and mass rather than size and weight. It sounds more science-y that way.

What do we call it when there are two things interfere with each other ? That's right, a relationship !

... more to come...