Yummy Gummi Bear

September 9, 2005

Period 1


“Investigation of the Squishiness of Gummi Bears”



One of the characteristics of gummi bears that makes them interesting and fun is their ‘squishiness’.  It can be observed that the squishiness of a gummi bear may change depending on certain conditions.  It is believed that temperature is one such factor that may have an effect on this property. The purpose of this experiment was to investigate the effect that temperature has on the squishiness of gummi bears, or degree to which a gummi bear will squash or flatten out. 


Since heat has a tendency to make materials softer, it is hypothesized that exposure to sunlight and a freezer will affect the squishiness of the gummi bears.  Therefore, the hypothesis for this experiment was “If the temperature of the gummi bear increases, then the squishiness of the gummi bear will also increase.”


One of the obstacles in designing this lab was to figure out a way to measure the ‘squishiness’ of a gummi bear, since this is not one of the standard things that we measure like mass or volume.  Therefore, we defined ‘squishiness’ as the ease in which a gummi bear can be flattened and decided to measure the force needed to be used on a gummi bear to cause it to flatten out.  Even then, it was difficult to decide when to record the force as the force will change during the squishing process.



In this experiment, 15 gummi bears of various colors, one spring scale, one freezer, and one sunlit window were used. 



Three sets of five gummi bears were used in this experiment.  The first set was placed in a freezer for five hours prior to the experiment.  The second set was allowed to remain at room temperature.  The third set was placed on the counter next to a sunlit window for five hours.  A thermometer was placed next to each group of gummi for the five hours and the temperarture of each thermometer was recorded at the end of that time.


The squishiness of the gummi bears was measured by taking one gummi bear at a time and pressing down on it with a spring scale.  To do this, the gummi bear was placed belly-up on the table.  Then, the spring scale was carefully placed on the center of the highest part of the belly of the gummi bear as in Figure 1.


Figure 1


Pressure was slowly applied on the gummi bear by pressing down on the spring scale until the gummi bear stopped changing shape.  The highest force observed during this process was recorded (measured in Newtons) . This process was repeated for each of the 15 gummi bears.





The results of the experiment were as follows:



Table 1:  Squishiness of Gummi Bears at Different Temperatures

Gummi Bear Temperature (°C)

Measured Squishiness (Newtons)

Average Squishiness (Newtons)


Bear #1

Bear #2

Bear #3

Bear #4

Bear #5


0  °C







25 °C







50 °C










Graph 1:  The Effect of Temperature on the Squishiness of Gummi Bears.


















The result of this experiment is pretty conclusive as there was a clear pattern that emerged between the temperature of the gummi bears and the force needed to squish them.  Every one of our 5 gummi bears tested at the lowest temperature required a force that was significantly higher than all of the other gummi bears tested, while every one of the 5 bears tested at the highest temperature required less force to squish than all of the other bears. The results for each trial at the same temperature were all within 0.6 newtons of each other indicating that the experiment has pretty good precision.


A graph of the average force needed to squish the gummi bears vs the gummi bear temperature results in linear downward pattern, which indicates that temperature and force needed to squish gummi bears are indirectly related. 


In terms of ‘squishiness’; a more ‘squishy’ gummi bear will be softer and require less force to squish.  Therefore, our gummi bears at the highest temperature were the most ‘squishy’ since they required the lowest force and the coldest gummi bears were the least ‘squishy’ since they required the most force.  We can then conclude that as the temperature of the gummi bears increased, the squishiness of the gummi bears also increased.  Therefore, the initial hypothesis was supported by the data collected. 


One of the most significant sources of experimental error in this experiment was due to the way the force needed to squish each bear was measured.  When pushing down with the spring scale, we watched carefully to only record measurements while the bear was still changing shape. Once the bear was completely flattened (no longer changing shape), the force reading on the spring scale became very high since the bear was as flat as it was going to get and we were then measuring the force being applied to the table.  It was quite possible that we did not judge when to stop making this measurement correctly.  If we recorded the measurement too late, then our force would be higher than what it should have been and would indicate that a bear is less squishy than it really is.  To get a more accurate measurement of the force, we could record a slow motion video of the process of pushing the spring scale.  We would need to include both the bear and the spring scale in the video.  Then we could analyze the video to see exactly when the bear stopped changing shape and what the force reading was at that exact moment.


Another error present in this experiment could have resulted from the fact that   mixed colors of gummi bears were used. This may cause an error in the 5 gummi bears that were heated with the sunlight due to the fact that different colors absorb heat differently.  It is likely that the darker colors absorbed more of the heat from the sunlight than the lighter colors and were therefore at a higher temperature than the lighter bears when tested.  This would have resulted in the temperature recorded not being accurate. In the future, this experiment could be performed using gummi bears that are all the same color to prevent this fluctuation.


Another source of possible error in this experiment results from the way the temperature of the gummi bears was determined.  The thermometer was never placed directly in or on the gummi bears.  We just assumed that the gummi bears would be the same temperature as the air around them.  While this assumption was probably quite accurate for the room temperature and the freezer gummies, it may not have been accurate for the sunlight gummies.  It is possible that those bears absorbed more of the radiant energy than the air and were at a higher temperature than the air around them, resulting in a lower recorded temperature of the gummies than they actually were.  To get a more accurate temperature, a 6th gummi could be used in each group with a thermometer inserted into it. This gummi bear would not be used for force testing as its structurally integrity would be compromised, but it would give us a more accurate measurement of the actual temperature of the bears.


 Although our results to seem to be valid and indicate a definite pattern, the experiment could be performed at more temperatures to see if the pattern is consistent.  Also we could test more bears to have more trials at each temperature.  An interesting further research question would be to compare the squishiness of one color to the squishiness of other colors of bears to see if the dyes used have any effect on the squishiness.