1A60.45 - Hoberman Devices

Code Number:
Demo Title:
Hoberman Devices
Area of Study:
Hoberman Sphere, MEGA Sphere, and Hoberman Flight Ring, Hoberman Ball.

Open or close the devices to show a relationship between volume and surface area.

The MEGA Sphere will open to a diameter of 4.5'.  However, as it is a little heavier in construction it may be a little more difficult to operate.  It can also be locked in the open position. 

Throw the ball into the air with a fast spin and it will flip to the other color.

  • Blane Baker, "Using an Expandable Toy in Discussing Rotational Motion", TPT, Vol. 43, # 4, Apr. 2005, p. 247.
  • Ivars Peterson, "Surreal Spheres", How it Works - Science Supplement, Spring 2000, p. 212- 215.


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