Science Buddies: "Ask an Expert"

We are confused as to whether we need to cut the abs pipe. We know we need to dunk the column at least up to the 6 ft mark, and then we need a few feet to hold on to the pipe. The instructions below are confusing. They say to measure the distance between the pool edge to the start of the water, but then say that it has to be a min of 5 ft and to record at 5 ft regardless of the actual distance. So should we leave the abs pipe at 10 ft? That gives about 4 feet to hold on to from the 6 ft mark on the pipe? Or should we cut it?

"Once you have found an acceptable location, use your tape measure to measure the distance between the boat slip, pool edge, or pier and the surface of the water. You can imagine that the length of the whole tape measure will be the length of the oscillating water column. Mark the distance down in your lab notebook. Record the distance as a minimum of 5 feet in your lab notebook, even if the actual distance is less than 5 feet. This is the minimum value required to construct a functioning oscillating water column for this science project.
Once you've returned home, use the tape measure and mark the value that you recorded in step 2 on the ABS pipe with the rubber band. Now add 3 feet to where the first rubber band is placed. Place a second rubber band at this location. Remove the first rubber band. The purpose of this extra few feet is to give you bleep to hold on to while you are dunking the oscillating water column."

Moderator note: Project link: https://www.sciencebuddies.org/science- ... cean-waves

Hello,

This is an interesting project and thanks for your patience waiting for a reply.

If your distance is greater than 5 feet, you should use your measured distance and add 3 feet.

This sentence from step 2 in the project only applies if your actual distance is less than 5 feet.

Record the distance as a minimum of 5 feet in your lab notebook, even if the actual distance is less than 5 feet.

The next sentence in step 2 explains why you would use 5 feet rather than your measurement IF and only IF your measurement was less that 5 feet:

This is the minimum value required to construct a functioning oscillating water column for this science project.

It sounds like your measurement was 6 feet? In that case, use your measurement since it is greater than 5 feet ... and proceed with the instructions in step 3!

Let us know if this helps clarify those 2 steps and be sure to let us know if you have more questions!

Thank you again for your patience!

Madeline