Category Archives: Dynamics Of Fluids

Constant Velocity Tubes

Demo: FM-C-VT
Pira Index: 2C 30.25

Lab Equipment  Directions
  1. Mounted velocity tubes
Note: The red, orange, and yellow tubes contain CHEVRON Hydraulic oil AW ISO 22. The green, blue, and violet tubes contain CITGO A/W Hydraulic Oil 46.
If tubes break – thoroughly wash and rinse any body part that may have touched the substance.
  1. Invert the tubes and watch the bubble rise at different times.
  2. Have students time the bubbles and plot graphs of position versus time.

Two – Liter Smoke Rings

Demo: FM-C-TL
Pira Index: 2C 50.15

Lab Equipment  Directions
  1. plastic drinking bottle
  2. incense stick and matches
  3. propane torch
  4. 35mm projector (or OHP)
(can also use large drinking cup with circular hole cut in bottom and balloon rubber stretched over the open end)
  1.  Light two inches of the incense stick with the torch.
  2. Place burning stick into bottle held upside down.
  3. Fill the bottle with smoke.
  4. Turn off room lights and use 35mm or OHP to make the smoke more visible.
  5. Remove stick and hold the bottle upright and squeeze.

Note: small easy squeezes work best.

Bernoulli’s Principle

Demo: FM-C-BP
Pira Index: 2C 20.40

 Lab Equipment  Directions
  1. index card with thumbtack
  2. open cylinder with flange
  3. stopper and adaptor for hose fitting
  4. funnel
  5. ping pong ball
  6. Pasco air source and hose
  1. Connect the cylinder to the air supply.
  2. Hold the index card under the cylinder with the thumbtack pointed up, turn on the air supply and let go of the card.
  3. The cardboard should stay suspended under the flange while air is being blown out.
  4. Turn the air output dial to zero and hold hose in a vertical position. Place ping pong ball above top of hose and turn dial up until ping pong floats in air column.
  5. Connect funnel to air hose and turn upside down as shown. Place ping pong ball in the funnel to show that it doesn’t fall out.