• a centrifuge is a device that spins rapidly and is used to separate substances by density, as well as simulate the effects of gravity
  • a spinning centrifuge applies a centrifugal force to the objects it contains
• a rotating frame of reference is the frame of reference of any object moving in a circle
• centrifugal force is a fictitious force used to explain the outward force observed in a rotating frame of reference
• making a spacecraft rotate at the appropriate frequency can simulate gravity equal to Earth's gravity