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After taking the basic measurements of rubber ducks, the hard-hitting investigative reporters at RubaDuck asked a very basic question: If I was lost at sea, would my rubber duck be floaty enough to support my iPod? Not being ones to ignore important pseudo-socio-scientific questions such as these, we decided to tackle the engineering required.  Calculations and force diagrams were penned onto a local coffee house napkin. The coffee-stained results yielded the following diagram:

Essentially when we asked, "how floaty are rubber ducks?", we were asking what's the difference between the "floaty" force* and the weight of the duck?  Since the "floaty" force is simply the weight of the displaced water (we're believing NASA and Archimedes on this one), you can get the "floaty" force by multiplying the volume of the duck by the specific gravity of water (0.0098 N/ml @ 60 C).  And then it's simply a matter of subtracting the weight to get the "floatyness" of a duck:

"floatyness" = "floaty" force - weight

* - If you object to the use of the term "floaty" and think we should have used a term more like "buoyant", please contact Roger and tell him about it in 1,000 words or more.

Here are the numbers for our willing volunteers:

Tabulated Buoyancy Calculations (The Hard Data)

Weight (grams) Volume (ml) "Floaty" Force (N) "Floatyness" (N)
65 150 1.500 0.830
35 50 0.490 0.150
50 150 1.500 1.000
40 45 0.440 0.100
40 75 0.730 0.340
40 75 0.730 0.340
40 75 0.730 0.340
15 25 0.240 0.100
50 50 0.490 0.000
20 50 0.490 0.290
20 50 0.490 0.290
15 20 0.200 0.100
45 150 1.500 1.000
15 45 0.440 0.290

Data taken November 11, 2005 by DevilDucky with Ducklips as official data recorder
 and Roger was "El Jefe" for the project.

Buoyancy Statistics

Average Rubber Duck Buoyancy:  0.08 lb

Standard RubaDuck statistics disclaimer: "We realize that running statistics on rubber ducks is probably some sort of blasphemy but we take our chances and forge ahead anyhow."


After much work and pencil scratching we have found that, if fully immersed, the average rubber duck will be pushed upward with approximately 0.08 lb of force.  This is not a large amount of force.  For comparison, this is about 7 U.S. quarters, about 36 paper clips, or (to really put in perspective) one iPod nano.

So what does this mean to you?  This means that if you weigh 160 lbs, it would take about two thousand of your rubber duckie friends to keep you high and dry if your boat sank.  We're not going to attempt to figure out how you would harness two thousand rubber ducks together to do this, but you get the picture.  Oh, and if it was you and your iPod, it would take 2,001.