- 1). Determine the point in the test tube at which to calculate the RCF; measure the radius of the tube, in millimeters, at that point. Call this distance "r" and record it for later use.
- 2). Substitute the values for rpm and r into the formula for Relative Centrifugal Force:
RCF = 1.12r (rpm/1,000)^2.
For example, with an rpm of 200 and an r value of 30, the formula becomes:
RCF = (1.12 x 30) x (200/1,000)^2. - 3). Reduce the equation to calculate the RCF value. Using the example in the previous step, the equation reduces to:
RCF = 33.6 x (0.2)^2
This further resolves to 1.1344. The resulting RCF is the rpm value converted to relative centrifugal force.
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