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rpm/ g : how to calculate? - Does anyone know the formula? (Dec/01/2006 )

Hi,

I learnt but forget the way one can calculate rpm to g of the centrifuge...

ph34r.gif

-yeping-

I pefer to use a nomograph, but I don't have an electronic version to send you.
here is the formula :

rcf = 0.00001118 x r x rpm x rpm

rcf is g
r is the rotating radius in cm
rpm is revolution per minute

-Missele-

u mean convert rpm to g?

if that's the case, here's the forumula:

g = (1.118 exp (-5) ) R S²

g could also be found under the name RCF (Relative Centrifugal Force)

1.118 exp (-5) means 1.118 x 10 to the power of -5...just couldn't find a better way to write it...

EDIT: R is the radius of the rotor in centimeters, S is the speed of the centrifuge in revolutions per minute...

-Property of Yulia-

http://www.protocol-online.org/cgi-bin/prot/jump.cgi?ID=1864

-K.B.-

is not 'Property of Yulia' and Missele are saying the same thing???

-T. reesei-

QUOTE (T. reesei @ Dec 2 2006, 02:03 PM)
is not 'Property of Yulia' and Missele are saying the same thing???


almost, but in different syntax...choose whichever u feel comfortable with wink.gif

the more options u have the easier it is to find the solution...

-Property of Yulia-

yea ............thank u

-T. reesei-

check the catalogue of your centrifuge and rotor. many times they have a table of rpm verses g.

-Kathy-