We found, however, that our prediction was close, but not
quite right. We predicted that weight 2 would be the slowest. In fact, it
was the fastest.
about our hypothesis, I had ventured that weight 2 could conceivably be the
fastest. We thought that the rounded end might push the water behind it.
But we couldn’t
explain it well, and we didn’t really believe it would have the least
drag. Whether our reasoning was true or not, we were surprised to find that
it had the
quickest time of all three weights. Our initial reasoning for putting weight
3 as the most hydrodynamic was its resemblance of a submarine. The fact that
almost all submarines are shaped like that, and considering that submarines
depend on minimal amounts of drag, we figured that the engineers must have
a very compelling
reason for shaping them that way. Here is our result table for our average
times for each weight.
As you can tell, weight 2 had the least drag, weight 3 the
second least, and weight 1 the most. We had thought that the object with
the least frontal surface
area usually had the least drag, but weight 3 had
an area of .5625 sq. in. while weight 2 had an area of 1 sq. in. We suppose
that the frontal surface area is
not the only factor in hydrodynamics.
Our only regret about the experiment is that we only used three weights. We tried very hard to get more weights, but all the stores only had three choices. We called five different fishing stores, but none of them had a large supply of one pound fishing weights.
Background by Nora