2a10.35a.jpg

 

Code Number: 2A10.35

Demo Title: Cohesion Plates

Condition: Good

Principle: Cohension

Area of Study: Fluids

Equipment:

Cohesion plate with handles, water, masses.

Procedure:

Press the dry cohesion plates together.  While you can feel that it takes some force to pull them apart, it will not be enough to hold one plate up against the other.  Apply a little water to one plate and then press them together.  You will now be able to hang significant mass from the handle of one of the plates.

References:

  • Thomas B. Greenslade, Jr., "Adhesion Plates (photo)", AJP, Vol. 76, # 2, February 2008, p. 157.
  • Donald D. Snyder and Bruce E. Lee, "Cohesion Plates and Convection Currents", AJP, Vol. 32, #1, Jan. 1964, p. 61.
  • George M. Hopkins', "Surface Tension.", Experimental Science, Volume Two, p. 229.
  • Martin Gardner, "Invisible Glue", Science Tricks, p. 18
  • Julius Sumner Miller, Q186 & A186, Millergrams II – Some More Enchanting Questions for Enquiring Minds, p. 50 & 103.
  • Joseph Frick, "# 76 - Adhesion", Physical Technics: Or, Practical Instructions for Making Experiments in Physics and the Construction of Physical Apparatus with the Most Limited Means, p. 82.
  • "Adhesion Plates", Pike's Illustrated Catalogue of Scientific & Medical Instruments, 1984, p. 141.