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300 × g to RPM

300 × g at common rotor radii

Rotor radiusSpeed to set
5 cm2,317 RPM
6 cm2,115 RPM
7 cm1,958 RPM
8 cm1,831 RPM
8.5 cm1,777 RPM
9 cm1,727 RPM
10 cm1,638 RPM
12 cm1,495 RPM
15 cm1,338 RPM
20 cm1,158 RPM

How to set a centrifuge to 300 × g

  1. Find the radius of your rotor in cm, from the centre of the rotor to the bottom of the tube. It is printed on the rotor or in its manual. Enter it above; 300 × g is already filled in.
  2. The RPM to set is shown as you type. The table below gives it for common radii.
  3. Set the centrifuge to that RPM, or enter the × g directly if it has an RCF mode.

Frequently asked questions

How many RPM is 300 × g?

It depends on the rotor. At an 8.5 cm radius, typical for a microcentrifuge, 300 × g is about 1,777 RPM; at 10 cm it is about 1,638 RPM. The formula is RPM = √(RCF ÷ (1.118 × 10⁻⁵ × r)), with r in cm.

Is 300 g the same as 300 RCF?

Yes. RCF, relative centrifugal force, is written as a multiple of g, so 300 × g, 300 RCF and 300 g all mean the same force.

Why does a bigger rotor need fewer RPM?

Force grows in proportion to the radius, so a rotor twice the size reaches 300 × g at 1,256 RPM of the speed (1 ÷ √2, about 71%).

Common centrifuge speeds

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