4C32.10 - Wet & Dry Bulb Hygrometer - Sling Psychrometer

Code Number:
4C32.10
Demo Title:
Wet & Dry Bulb Hygrometer - Sling Psychrometer
Condition:
Excellent
Principle:
Vapor Pressures/Partial Pressures
Area of Study:
Heat & Fluids
Equipment:
Wet and Dry Bulb Hygrometer and Water.
Procedure:

Wet the cloth that is on the end of one thermometer with water.  Rotate the thermometer pair vigorously until the wet thermometer will not go any lower.  Read the difference between the two thermometers and consult the relative humidity chart.

References:
  • Paul Hewitt, "Answer to September Figuring Physics Question", TPT, Vol. 53, #7, Oct. 2015, p. 442.
  • F. Esmael, "Humidity Graphs for All Seasons", TPT, Vol. 20, #9, Dec. 1982, p. 612.
  • "Atmospheric Humidity", TPT, Vol. 17, #8, Nov. 1979, p. 538.
  • Carson I. A. Ritchie, "Weather House", Making Scientific Toys, p. 117.
  • Unesco, "A Wet and Dry Bulb Hygrometer", 700 Science Experiments, p. 94 - 95.
  • Janice VanCleave,  "Wet Bulb",  Earth Science for Every Kid - 101 Easy Experiments That Really Work, p. 148 - 149.
  • Julius Sumner Miller, Q228 & A228, Millergrams II – Some More Enchanting Questions for Enquiring Minds, p. 71 & 118.

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