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Assume v. Presume

Stirrer! m² is pronounced "square metres". A 2 metre square has an area of 4 square metres. And that's that.

(snap, and Trev needs to sort out the difference between a meter and a metre)
 
And even if it was "metres squared" (which it might have been, hard to tell), 2 metres squared still has an area of 4 square metres. I did this kind of stuff at school, where was everyone else?
 
Black Hole said:
You're right, it was. OK, 6'6¾" square is 43.07 sq.ft.
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And I bet you needed a slide rule to work that out!

I dispute that m² is "square metres" as to me it was always "metres squared. What would an acceleration of 10 square metres a second feel like, I ask myself?

We also say "square" and "squared" interchangeably so you don't have a gas meter to stand on IMHO!

(I do love these pointless arguments!)

Edit: Whoops! That's viscosity, isn't it?
 
@Mike.
And I bet you needed a slide rule to work that out!
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No. Although I did use a slide rule, they were not very good at feet and inches.

Don't be even sillier, metres don't accelerate and even if they did it would be the seconds that were squared.
We also say "square" and "squared" interchangeably
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Not if we want to be unambiguous we don't, especially if we chuck in a double negatives
 
4291 said:
That would be velocity. M/S squared (can't type the power) would be acceleration.
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You can do it by copy-and-paste from an existing post, or for iOS there are several Unicode character map apps - eg "Character Pad". It's a bummer that iOS is so locked down we can't have accessory keyboards (outside their native app).
 
Trev said:
@Mike.

Don't be even sillier, metres don't accelerate and even if they did it would be the seconds that were squared.
Click to expand...

So what is a square second? s² (s square[d]) is a dimension, but I have no concept of a square second. Or per square second.

Anyway, all this arose from someone saying x m² as "x metres square(d)" rather than "x square metres," and you seeing it as ambiguous, ie, (x m)² vs x (m²). But who says "x metres per square second?" Nobody! (Apart from you, Black Hole, when observing your accretion disk.)
 
Black Hole said:
You can do it by copy-and-paste from an existing post, or for iOS there are several Unicode character map apps - eg "Character Pad". It's a bummer that iOS is so locked down we can't have accessory keyboards (outside their native app).
Click to expand...

http://osxdaily.com/2013/06/03/symbols-glyphs-characters-ios-keyboard/



(Not that I generally give help with iOS.)

In Windoze, there is Character Map, but there is a paucity of powers there. In fact, you can't do anything other than ⁰¹²³⁴⁵⁶⁷⁸⁹⁺₀₁₂₃₄₅₆₇₈₉₊₋₌₍₎ which is very limiting. I can't raise anything to power n, for instance, or s to power -2.
 
It's x m/sec squared I suppose. It's the (m/sec) that is squared not the seconds as I originally implied. Anyway, why can't you square seconds? It's only a number. Ok so s is a constant, but so is c and you can square that.
 
Trev said:
It's x m/sec squared I suppose. It's the (m/sec) that is squared not the seconds as I originally implied. Anyway, why can't you square seconds? It's only a number. Ok so s is a constant, but so is c and you can square that.
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You were right the first time, assuming you meant acceleration.
$m s^{-2}$ in TeX , or m/s².
metres times (seconds to power -2) which is impossible for me to type into this! :mad:

So, E=mc² would be "E equals m square c" for Black Hole? Nah! Black Holes should know better.

And a second isn't a number! But the "1" in "1 second" is a number.
 
Ah of course. It's often quoted as 'metres per second per second, so it is the seconds that are squared:) . I'm pleased that I took the time for you to sort that one.
 
Why did they choose c to be the universal constant which then had to be squared when used in the famous equation which made it famous? After all it is just a number used to make the arithmetic work out to the answer people want it to be (which I am not totally convinced *is* the right answer).
 
gomez² said:
Why did they choose c to be the universal constant which then had to be squared when used in the famous equation which made it famous? After all it is just a number used to make the arithmetic work out to the answer people want it to be (which I am not totally convinced *is* the right answer).
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Because it is the speed of light? (Which I prefer to be 1, but it makes mundane travel on Earth over fussy about decimal places.

c squared is the quantity that appears in the energy formula, true, and the Fitzgerald Lorentz transformations.

Why are you not convinced by the right answer, by the way?
 
Because the standard model predicts a universe which has many times the energy and mass that is detectable. Fudging and fiddling with the model reminds me of the attempts to model the paths of the planets in the sky when people could not accept that the Earth was not the centre around which everything else turned. We are still, literally and metaphorically, groping in the dark towards full understanding of how the universe really works.
 
gomezz said:
Because the standard model predicts a universe which has many times the energy and mass that is detectable. Fudging and fiddling with the model reminds me of the attempts to model the paths of the planets in the sky when people could not accept that the Earth was not the centre around which everything else turned. We are still, literally and metaphorically, groping in the dark towards full understanding of how the universe really works.
Click to expand...


I see that as another problem, but c seems to be an immutable constant except possibly at the extremity of the big bang or at quantum levels, is that what you meant?

What I find hard to grasp is the idea that someone travelling in Special Relativity at near the speed of light relative to nearby objects, who sees the whole universe concentrated into a tiny spot of ultra-violet radiation ahead of him, is not in some way special, relative to the rest of us. I suppose the answer is that Special Relativity is untenable by itself, you have to include General Relativity to make sense of it, and then all those other (stationary!) objects in the rest of the universe make that speedster special, and unique, in his experience.
 
Trev said:
@Mike.
No. Although I did use a slide rule, they were not very good at feet and inches.
Click to expand...
I used one in my younger days for estimating in the paper trade, Double Demy etc, but it was a beggar when they went metric in the late '60's.
 
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