Constant Acceleration Equation  physicist please!by Gregor Tags: acceleration, constant, equation, physicist 

#73
Mar1206, 07:12 PM

P: 39

however this is just a conversion formula in my demonstrations I've used prefixed units for simplicity, however these units are consistant throughout each expression 



#74
Mar1206, 07:14 PM

P: 4,780

g, m, and s DO NOT FOLLOW THE RELATIONSHIP g= a*s² How many times do I have to tell you that? 



#75
Mar1206, 07:17 PM

P: 39

I should tell you that English is not my first language (ich bin Deutscher) so sometimes things get lost in the translation %/ I know a drug store is what we call an Apotheke 



#76
Mar1206, 07:18 PM

P: 4,780

That was not for you, that was for Vey2000, and it was not supposed to be funny.




#77
Mar1206, 07:23 PM

P: 39

the only importance for the formula is that it produces the correct numerical value for 1 g in revised units and the forumula does this perfectly as I have demonstrated several times (to the annoyance of every physicist in the forums) 



#78
Mar1206, 07:33 PM

P: 4,780

You do NOT realize it. Look, 3 + 2 = 5 right? does 3(apples) + 2(oranges) = 5 (apples) No. Do you see my point? The math is right, the logic is WRONG! 



#79
Mar1206, 08:05 PM

P: 39

yes, I've seen the point all along however it's my point that is being missed 9.80665 (Z) * 0.001 (I) * 0.001 (I) = 0.00000980665 (N) there are no apples, oranges, or any physical entities here just numbers to be computed. the result (N) just happens to be equal to g when m = 1 meter and s = 0.001 second the result is always "numerically equal" to g it's just a convenient coincidence that the formula provides the correct numeric value, there is no direct connexion to physical dimensions involved. 



#80
Mar1206, 08:15 PM

P: 4,780





#81
Mar1206, 08:53 PM

P: 39

how are they wrong?
the only difference between 9.80665 * 0.001 * 0.001 = 0.00000980665 and 9.80665 m * 0.001 s * 0.001 s = 0.00000980665 m/0.001 s/0.001s is that the units are added in the last expression this does not make them "wrong", but simply "included" or "not included". the value for g is correct for these units nonetheless since 1 g does = 0.00000980665 m/0.001 s/0.001s 



#82
Mar1206, 09:11 PM

P: 4,780

Dammit are you blind?
9.80665 m * 0.001 s * 0.001 s = 0.00000980665 m/0.001 s/0.001s does [tex] ms^2 = \frac{m} {s^2}[/tex] to you? 



#83
Mar1306, 07:55 AM

P: 9

Unfortunately, it may be the case that despite taking the beltway I still got nowhere since Gregor is still confused. Allow me to take a stab at "fixing" your first equation. What you really have is the following: 9.8 m/s^2 * 0.001 (s/s') * 0.001 (s/s') = 9.8x10^6 m/s'^2 Notice how there are indeed units in there? Notice how s cancels out with s in the left hand side and you are left with s' instead? Now I'll take a stab at interpreting your second "equation." The two "0.001 s" divisors are in fact the new s' units. Replace it in the right hand side of my proposed equation and you'll recover the right hand side of your second "equation." So the problem clearly lies in the left hand side. What you are doing by multiplying on the left side by "time" is actually in fact multiplying by the time unit conversion factors  0.001 s/s'. This relates to my previous post where I went out of my way to explicitly show you the conversion factors as variables. The other problem is that on the left hand side you have "assigned" 9.8 the unit of m, whereas it is m/s^2. So, your "formula" is g' = g * T'^2, where g' is just g in the new units of m/s'^2, and T' is the conversion factor with units of s/s'. This is mathematically consistent. You have to realize that just because things work out in your mind does not mean that what comes out into paper works out the way you write it. As I said, in my opinion the problem was one of definitions. 


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