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Convert g into rpm - (Jun/25/2007 )

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Just wondering...

How to convert g into rpm?
500xg
1000xg
10,000g

Thanks in advance.

-Minnie Mouse-

g=(1.118x10^-5).R.s^2
where r is the radius of the rotor in cm and s is the speed in rpm.

s=sqrt( (1.118x10^5xg)/r )

-swanny-

QUOTE (swanny @ Jun 26 2007, 09:53 AM)
g=(1.118x10^-5).R.s^2
where r is the radius of the rotor in cm and s is the speed in rpm.

s=sqrt( (1.118x10^5xg)/r )


Go to the Beckman website and check or look at their catalogue. They have the rotors' radius there and also instruction about how to calculate g... If you are using other types of rotor then check the appropriate producer's catalogue. Calculating g may also depends on where your centrifuged particles are, e.g. the g for the pellet at the bottom of the tube is different from the g of the particles at the middle of the tube (if you are doing sucrose cushion or gradient for example)

-Almasy-

Thank you swanny and Almasy smile.gif.

-Minnie Mouse-

QUOTE (Minnie Mouse @ Jun 25 2007, 10:59 PM)
Thank you swanny and Almasy smile.gif.



For most centrifuges these days the displays have g and RPM. High speed floor standing and ultracentrifuges have automatic rotor recognition and also have duplicate displays.
The manuals also have a conversion table which has 3 parallel axis, one for g, one for RPM and one for the rotor radius. Get a ruler and if you know 2 of the 3 parameters then you can find the third number by whereit bisects the third axis.

-Rhombus-

Thank you Rhombus smile.gif.

-Minnie Mouse-

QUOTE (Minnie Mouse @ Jun 27 2007, 05:44 AM)
Thank you Rhombus smile.gif.


Hai,
U can even do it online using the converter
http://www.beckmancoulter.com/resourcecent...s/rotorcalc.asp

-manojbmenon-

Thank you manojbmenon for the link smile.gif

-Minnie Mouse-

Try this site:

http://www.eppendorf.ca/support/online-calculator.asp

might help!

-SLAR-

Hello
Yes, now a days most of centrifuges have both "g" and "rpm" marks in the machine. U can change either option accordingly.
Thanks

-Arunlovy-

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