I can stop any time I want to....

[johnpalmer]

So, I bought a Freshman Physics book. And I started working problems. And I was appalled.

I didn't have a scientific calculator! Well, there are Android apps for that - so, that's fixed.

Then I found how hard it is to sketch vector diagrams on lined paper. Wait - how did I not have large quantities of graph paper around? (Any old D&D enthusiast could ask the same question. I still have my polyhedral dice, though!) And I couldn't lay my hands on my scale! (Um - those triangle-cylindrical rulers that let you measure to different scales.) That's not *critical* - but a scale can really help one make a more accurate sketch. Technically, you could use a ruler, "this line is kinda like 3 times that one" but a scale just makes that easier.)

There - I now have them, and some extra mechanical pencils to boot.

But I did not get triangles, a compass, etc.. Yet. (Yes, yes, I also haven't had time to paint it or build it to scale....)

I'm done with vectors - trig is easy, after all.

(Ouch. I may have made some enemies with that - remember, I majored in math!)

I even figured out my problem on the one question that had the rounding error - one answer came out to something like 7.83 and the other came out to 7.858 - so, yes, rounding to 2 significant figures would introduce a difference in the answers of .1, which makes perfect sense - the actual difference was less than .03, so both answers were correct, within the margin of error.

Time to "move on". (Hah! Get it? Because the next section is *motion*! I'm *moving on*... okay, I guess I'm taking high school nerd too far now, aren't I?)

Seriously, this is good and therapeutic... I wish I'd taken physics after I started acing math classes, because I just barely remember it, and it was never quite as interesting as it seems to be when I'm following the math in my head.

Comments

[anisoptera.livejournal.com]

I cannot picture what a "triangle-cylindrical ruler" looks like. Did you mean this http://www.pasthorizonstools.com/Triangular_Scale_Ruler_p/sr001.htm?

[johnpalmer.livejournal.com]

Yes, that's it. You could call it "triangular" but my inner geek was flying high - a triangle is a two dimensional object. Scales are one of those things that everyone knows if they've used one, and nearly no one knows if they haven't.

The point of them is that each different edge has a different scale (ratio of length in the drawing to length in real life), so you have a bunch of different scales in one tool. (Or maybe you already knew that?)

[anisoptera.livejournal.com]

I think I might have used one 30 years ago in a shop class I took at a community college. I wasn't allowed to take machine shop in high school and I took the opportunity to do so when I worked for a company that would pay for it. :)