Mi-1 Rotating Stool


To demonstrate the conservation of angular momentum.


  • Rotating stool
  • Dumbbell weight
  • Bicycle wheel

Rotating Stool Rotating Stool Diagram

Rotating Stool and Diagram.


A volunteer student is seated upon the stool holding a dumbbell weight in each hand close to the body. The stool is rotated slowly. The student then outstretches his/her arms and the redistribution of mass requires a change in rotational speed to conserve angular momentum. If initially the student has his/her hands outstretched when the weights are brought in toward the body the increase in rotational speed can be large enough to make it almost impossible to stay seated.


To be added.