Uploaded February 2021 | Updated September 2026, 2 weeks ago
This is one in a set of 2 videos which can be used to determine the relationship between the velocity of a liquid moving inside a pipe with a changing diameter. In each video a 2” or 3” pipe is filled with water and oriented vertically. Water flows out of a smaller hole (¼”) near the bottom of the larger pipe.
Fluid Flow Lab (NO Measurements): youtu.be/dR5IzR7wXYw
Fluid Flow Lab (Data Set #1): youtu.be/04jRKYa0cjE
Fluid Flow Lab (Data Set #2): youtu.be/hF4FHi_HdHc
Data Collection and Calculations:
The vertical position of the water level in the clear pipe and the time can be used to estimate the instantaneous velocity of the water moving through the larger pipe. The velocity of the water leaving the pipe through the smaller diameter hole can be estimated using the horizontal displacement of the water while falling 0.5m to the ground. Consider each water droplet is a projectile with zero horizontal acceleration and a vertical acceleration of -9.8m/s/s. Use the measured horizontal displacement and the vertical displacement of -0.5m to solve for the initial horizontal velocity of the water when leaving the pipe.
Data Analysis:
Graph the velocity of the water moving through the larger pipe on the y-axis and the velocity of the water moving through the smaller diameter hole near the bottom on the x-axis. Consider the significance or meaning of the slope of the graph and the y-intercept of the graph.
Lab Extension:
Have the students graph the height of the fluid above the exit hole on the x-axis and the velocity of the water leaving the smaller diameter hole near the bottom on the y-axis. A discussion of the resulting equation and the meaning of the slope can lead into the topic of energy conservation with moving fluids. This can also introduce the topic of “energy density” in fluids which can be used to derive Bernoulli’s equation. .
This is one in a set of 2 videos which can be used to determine the relationship between the velocity of a liquid moving inside a pipe with a changing diameter. In each video a 2” or 3” pipe is filled with water and oriented vertically. Water flows out of a smaller hole (¼”) near the bottom of the larger pipe.
Fluid Flow Lab (NO Measurements): youtu.be/dR5IzR7wXYw
Fluid Flow Lab (Data Set #1): youtu.be/04jRKYa0cjE
Fluid Flow Lab (Data Set #2): youtu.be/hF4FHi_HdHc
Data Collection and Calculations:
The vertical position of the water level in the clear pipe and the time can be used to estimate the instantaneous velocity of the water moving through the larger pipe. The velocity of the water leaving the pipe through the smaller diameter hole can be estimated using the horizontal displacement of the water while falling 0.5m to the ground. Consider each water droplet is a projectile with zero horizontal acceleration and a vertical acceleration of -9.8m/s/s. Use the measured horizontal displacement and the vertical displacement of -0.5m to solve for the initial horizontal velocity of the water when leaving the pipe.
Data Analysis:
Graph the velocity of the water moving through the larger pipe on the y-axis and the velocity of the water moving through the smaller diameter hole near the bottom on the x-axis. Consider the significance or meaning of the slope of the graph and the y-intercept of the graph.
Lab Extension:
Have the students graph the height of the fluid above the exit hole on the x-axis and the velocity of the water leaving the smaller diameter hole near the bottom on the y-axis. A discussion of the resulting equation and the meaning of the slope can lead into the topic of energy conservation with moving fluids. This can also introduce the topic of “energy density” in fluids which can be used to derive Bernoulli’s equation. .
