2B30.36 - Magbeburg Hemispheres - Suction Cups

Code Number:
Demo Title:
Magbeburg Hemispheres - Suction Cups
Air Presure
Area of Study:
Heat & Fluids
Magdeburg Hemispheres.

Press the cups together to squeeze the air out from between them.  They should be very difficult to pull apart.

Press the cups together and then rotate the handle on each one so that the two halves of the handle are together.  This will create a partial vacuum between the cups which will make them very difficult to separate.

  • Donald E. Shult, "Pulling Your Cups Apart!", TPT, Vol. 26, #7, Oct. 1988, p. 424.
  • Mike McIntosh, Ann Brandon, and Earl Zwicker, "Pressure and Force", TPT, Vol. 25, #8, Nov. 1987, p. 534.
  • Robert Ehrlich, "H.6. Pulling Two Plungers Apart", Turning the World Inside Out and 174 Other Simple Physics Demonstrations, p. 101 - 102.
  • Joseph Frick, "#4 - Magdeburg Hemispheres", Physical Technics: Or, Practical Instructions for Making Experiments in Physics and the Construction of Physical Apparatus with the Most Limited Means", p. 115.

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