Damn you mathematicians

Borodog · #1 03-01-2007, 12:09 AM

Started rotational kinematics in class today. Was again reminded of this bollocks:

s = r*theta

This, and all that follows from it, drives me [CENSORED] NUTS. Do you see why?

[img]/images/graemlins/mad.gif[/img]

flipdeadshot22 · #2 03-01-2007, 12:15 AM

So you're more of a linear motion type guy I take it? What course/level is this btw?

Duke · #3 03-01-2007, 12:26 AM

First instinct: you hate radians.

Second thought: Typically this is where students start getting greek letters shoved up their asses, and you don't like phi, so you use theta instead.

Third: Kids are used to degrees, and will start screwing everything up because they aren't yet comfortable with radians.

Siegmund · #4 03-01-2007, 01:00 AM

It could be worse. Borodog could have been one of those crazy chemistry teachers who think there is some merit in using the base-10 logarithm.

Duke · #5 03-01-2007, 01:08 AM

[ QUOTE ]
It could be worse. Borodog could have been one of those crazy chemistry teachers who think there is some merit in using the base-10 logarithm.

[/ QUOTE ]

I'm still not convinced that any of my possible explanations are correct, though I'm pretty sure that it involves the teaching aspect and not just the material itself.

holmansf · #6 03-01-2007, 01:47 AM

'cause s doesn't have units length*angle. Or at least that's my guess.

Borodog · #7 03-01-2007, 01:52 AM

[ QUOTE ]
'cause s doesn't have units length*angle. Or at least that's my guess.

[/ QUOTE ]

Bingo. The expression is dimensionally incorrect. I [censored] HATE THAT [censored].

Me for 1/2 the semester: UNITS UNITS UNITS UNITS!

Me 1/2 way through the semester: Uh, except . . .

Phil153 · #8 03-01-2007, 07:07 AM

[ QUOTE ]
[ QUOTE ]
'cause s doesn't have units length*angle. Or at least that's my guess.

[/ QUOTE ]

Bingo. The expression is dimensionally incorrect. I [censored] HATE THAT [censored].

Me for 1/2 the semester: UNITS UNITS UNITS UNITS!

Me 1/2 way through the semester: Uh, except . . .

[/ QUOTE ]
Borodog,

You should let the market decide the units, rather than imposing your centrally planned bureaucratic monopolist unit system.

Off topic non sequiturs about the evil government are annoying, no?

flipdeadshot22 · #9 03-01-2007, 08:29 AM

I don't understand. radians are dimensionless units of angular displacement. what can be so hard about teaching a bunch of 14 year olds about this? I didn't have much difficulty in learning about the concept of radians (not trying to brag.) Just break down the scientific justification of the radian measurement to these kids, i'm sure they'll follow.

bxb · #10 03-01-2007, 11:14 AM

All the formulas are the same as they are for regular kinematics cept different letters.