rotation

speed

False. The centrifuge is a machine with a compartment at the end of a rotating circular arm, used to simulate the physical stresses of space travel during astronaut training.

That sounds like density centrifugation...So, a centrifuge?

A centrifuge has holes to insert the centrifuge tubes in, a cap to secure the tubes inside, and a lid to protect both the samples and experimenter in case of malfunction. There is also typically a way to set the centrifuge speed and a power switch to turn the centrifuge on and off.