2C10.30 - Falling Water Stream

See paragraph one in the procedure section
Code Number:
Demo Title:
Falling Water Stream
Bernoulli's Principle
Area of Study:
Heat & Fluids
Old fashioned faucet, 0-150 VDC power supply, water pump on electric motor, bucket of water, and stand for bucket, and plastic wash tub.

Turn on the water pump to a speed where water flows smoothly out of the faucet.  NOTE:  all the air needs to be out of the line for this to work properly.  Adjust the speed so that the water flows smoothly and constricts as it falls downward.

  • A. Tan, "The Shape of Streamlined Tap Water Flow", TPT, Vol. 23, # 8, Nov. 1985, p. 494.
  • Vladimir Grubelnik, Marko Marhl, "Drop Formation In A Falling Stream of Liquid", AJP, Vol. 73, # 5, May 2005, p. 415.
  • 4.19:  Jearl Walker, "Bernoulli Effect", The Flying Circus of Physics with Answers, p. 80 & 253.
  • 6.7:  Robert Ehrlich, "Narrowing of a Descending Water Stream", Why Toast Lands Jelly-Side Down, p. 107.
  • Julius Sumner Miller, Q59 & A59, Millergrams I – Some Enchanting Questions for Enquiring Minds, p. 41 & 97.

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