||St. Matt's Deep Site|
Designing your own experiment can be more difficult than you
can imagine. From writing the perfect title to analyzing the data,
things can become complicated. Although the work can be hard,
the experience is very rewarding. From this simple lab we learned
about the refraction of light, how it is related to scuba diving
and how to analyze data and error.
Through our experiment we learned how refraction effects the appearances of objects through different mediums. Refraction is the bending of light as it passes through one conditions to another. An example of this would be sunlight shinning into a pool of water. The light passed from the surface (air) to the water (the medium) would be slightly bent. We also learned how the results of refraction effect how we see under water. Have you ever noticed how when you reach for the side of the pool, it is always a farther away then you think? This is because objects appear to be three- fourths of their actual distance.
Refraction also tricks the human eye into seeing objects 33%
larger than they really are. For instance, if a fisherman, on
the surface caught a fish in the water, the fish would appear
to be 1/3 larger than its actual size. See
Photos. The results of refraction also appear to effect the
perception of speed of a moving object. Since refraction under
water makes our eyes believe that there is a greater distance
between two points, it would appear as if an object moving between
the two points would cover a farther distance in a shorter amount
of time. Even though the time, speed and distance would remain
the same, the speed of the object would look faster. This knowledge
of refraction, helped us better define why and how our results
came out the way they did.
Three bottles were used to test how refraction through water effects the appearance of the squares on a checkerboard. The three bottle were round, square, and hexagonal. Before we tested to see how the checkerboard squares distorted, we measured the size of one individual square. Its height was 10 mm and its width was also 10 mm.
In the experiment, the first bottle we tested was round. By
looking at our results we came to several conclusions about how
light changes when shown through a rounded object. The dimensions
of the square on the checkerboard when looked through the round
bottle were 10 mm by 5 mm. When converted to percentages we found
that the width decreased by 50% and the height stayed the same.
These results came out this way for more than one reason. First,
since the glass is rounded we have found through research that
when light passes through the glass, it is rotated 180 degrees,
depending upon its focal point. The focal point is where the beams
of light cross one another. Consequently, when light is projected
at different distances, the focal point changes accordingly. When
applying this theory to our experiment, we found the focal point
was such that the checkerboard rotated a perfect 180 degrees.
In addition to working with the round bottle we found several
aspects of the square bottle that added to our knowledge of refraction.
The measurement results were 20 mm by 5 mm. The percentage results
was width decreasing by 50% and height increasing by 200%. We
took the dimensions of the square bottle's right hand corner,
which was slightly rounded. We have concluded that the reason
the width of the circular bottle and the square bottle were the
same because of the corner angles of the square bottle.
The hexagonal bottle was a bit more complicated than the round
and square glasses. We found that its width was 35 mm and the
height was 15 mm. When translated into percentages, the width
increased by 350% and the height increased by 150%. Though we
came out with concrete numbers and percents, we were unable to
find a pattern as to why the checkerboards squares distort like
they did. Our reasoning is that because light passed through two
angles of glass there were two different patterns, which led to
our results being unobservable.
Because of the way our experiment was built, error is certainly a factor. there are two kinds of error apparent in our experiment: human error, and equipment error. As far as human error is concerned, because of the processes that had to be carried out in conducting our experiment, our results were certainly affected. For example, the repetitive process of taking pictures might have been jolted, or simply not carried out the same way every time. Other examples of human error are: the amount of water that light passed through in the different containers and how the quantities differed, the possibility that climate could have changed throughout the experiment, and simply how reliable and accurate the experiment was set up.
Equipment error also played an important role in our project.
It is important to note the fact that we built our experiment
knowing we didn't have access to the most reliable, accurate equipment.
Because of this, it made it a greater challenge to have results
that were one hundred percent trustworthy. Examples of equipment
error are the cameras used, the containers used, and the chessboard
used. Lastly, as a result of human and equipment error, the finished
project did not turn out exactly how we planned, but we learned
important factors to consider when designing an experiment.
As with every project, when looked back on, there are always
things that could have done better or with more care. In the case
of our project, several things could have been improved. We found
our topic was difficult to illustrate because of the way it was
set up. However, considering the fact that we lacked superior
equipment, our results came out extremely accurate. We also found
that it was important to stay on schedule in designing our experiment.
Because we budgeted our time and stayed on task, it was easier
to deal with problems that might have set back schedule. Lastly,
it is important that you clearly understand your topic and the
principles behind it. Before designing and conducting your experiment,
make sure you read and learn about your topic so that it will
better help you interpret and understand your results and why
they came out the way they did.
In designing and conducting our experiment, we concluded that it was harder and more complicated than we imagined. Issues arose, and posed more of a challenge in completing our project. However, we learned many valuable things. We learned what it takes to have an experiment that is reliable and accurate. This process was interesting and enabled us to better grasp an understanding of what science really is.