# Need help with maths calculations - anyone good at maths? watch

1. The centrifugal force, gmax can be obtained from the following formula:

gmax = 1.12 r (RPM/1000)2 where r = radius of rotation in mm, RPM = revolutions per minute

Use this equation to determine at which speed in RPM the centrifuge must be run to obtain
12,000g when r = 8.0 cm. Show the workings of your calculation below:

This is how I worked it out but dont know if its right?
r= 8.0cm (8.0 x 10) = 80mm

gmax (12000g) = 1.12 x 80 x (RPM/1000)^2

12000G/1.12 x 80 x 1000 = 365.9625274

RPM = 366 revolution per minute
2. I think you have mixed up your nemerators and denominators in the process of using a calculator - the method below shows the correct way to do it and gives an answer of 11580 revs/min (ANSWER)

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