Sphere Volume.

03312016, 11:29 AM
Post: #1




Sphere Volume.
Hi,
All of us know that Sphere Volume is calculate like this : 4/3(PI*R^3) A short cut from Bill Kolb is : "240 'DR' R^3 *", But NASA (on his siteweb) say (PI*D^3)/6. It is more easy and less steps, even I dont' see how go from first formulae to NASA one ? Gérard. 

03312016, 11:56 AM
Post: #2




RE: Sphere Volume.
(03312016 11:29 AM)ggauny@live.fr Wrote: Hi, PI * R * R * R * 8/6 = PI * 2R * 2R * 2R * 1/6 Bernhard That's one small step for a man  one giant leap for mankind. 

03312016, 11:58 AM
Post: #3




RE: Sphere Volume.
Hi, Gérard,
Well, I forgot almost mt math after so much brain damage caused by good life and drinks... .) Let me try: V = 4/3 * PI * R^3 Also, we know that D = 2 * R; then R = D/2 If we replace R for D/2 in the initial equation, we get: V = 4/3 * PI * (D/2)^3 which can also be written as: V = 4/3 * PI * D^3 / 2^3 Or: V = 4/3 * PI * D^3 / 8 Or: V = 4/(3 * 8) * PI * D^3 Or: V = 4/24 * PI * D^3 Or: V = 1/6 * PI * D^3 Or: V = (PI * D^3)/6 Jose Mesquita RadioMuseum.org member 

03312016, 12:46 PM
Post: #4




RE: Sphere Volume.  
03312016, 02:23 PM
Post: #5




RE: Sphere Volume.
Of course I have see the answers, but me I find :
4/3(Pi*(D/2)^3) 8/6(3*Pi*(D/6)^3) and if I divise all by 6 I obtain : 8(3*Pi*D^3) so it is 24*Pi*D^3 and it is false ! desolation ! Gérard. 

03312016, 03:32 PM
Post: #6




RE: Sphere Volume.
when's the last time anyone had to fill a sphere with beer ??
(just askin', ) 2speed HP41CX,int2XMEM+ZEN, HPIL+DEVEL, HPIL+X/IO, I/R, 82143, 82163, 82162 25,35,45,55,65,67,70,80 

03312016, 04:17 PM
Post: #7




RE: Sphere Volume.
Of course I prefer drink the beer, it is less complicated then do theses calculs !
LOL. Gérard. 

03312016, 04:34 PM
Post: #8




RE: Sphere Volume.
(03312016 03:32 PM)TASP Wrote: when's the last time anyone had to fill a sphere with beer ?? You have just brought a lot of past memories to my mind, from my good old times spent in Ghent (Belgium) studying computer technologies and of course, drinking the famous Kwak beer. Not a complete sphere, but still it was great fun drinking it! Jose Mesquita RadioMuseum.org member 

03312016, 05:21 PM
Post: #9




RE: Sphere Volume.
The sphere thing is interesting from a computational standpoint, but I'm damned if I can think of a practical application. We've ruled out beer, what else is there ??
2speed HP41CX,int2XMEM+ZEN, HPIL+DEVEL, HPIL+X/IO, I/R, 82143, 82163, 82162 25,35,45,55,65,67,70,80 

03312016, 06:55 PM
Post: #10




RE: Sphere Volume.
Yes, if we are not careful all the beer on the face, same with glass like a boot of cowboy !
Gérard. 

03312016, 07:20 PM
Post: #11




RE: Sphere Volume.
(03312016 02:23 PM)ggauny@live.fr Wrote: Of course I have see the answers, but me I find : You obviously forgot some basic math rules. First of all, forget the brackets (except around d/2). All values are faktors, so there is no need to set brackets. Then, (a/b)^n = a^n / b^n. So... 4/3 * pi * (d/2)^3 = 4/3 * pi * d^3 / 2^3 = 4/3 * pi * d^3 / 8 = 4/3/8 * pi * d^3 = 4/24 * pi * d^3 = pi * d^3 / 6 Dieter 

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