The magic and mystery of Orbitz

Physics of the Mundane

Adam Johnston

Orbitz is a beverage produced by the Clearly Canadian Beverage Company.^[1]  The drink engineers of Clearly Canadian have discovered a way to suspend particles of flavoring, officially called Agel spheres,@ inside the liquid.  Apparently, the gel spheres can sit anywhere within the beverage without sinking, floating or any kind of stratification.  Thus, the theme of the beverage is, “Defy gravity.”  Although we will admit that the gels are awfully spiffy, we might hesitate to say that they can disobey a natural law. 

There are likely dozens of activities that can be done with the 99 cent bottles of Orbitz.  If your studies lead you in tangential directions or toward new discoveries, please follow such leads as well.

“Where do I start?”

Determine the Agravity defiance@ of the gel spheres:

Try to explain what allows the gel spheres to suspend in the liquid without sinking or floating, nor having any particular level in the liquid that they are more or less likely to stay.  You may want to try to create/engineer a liquid that will allow the gel spheres to neither float nor sink.  Or, you could alter the Orbitz liquid to determine the conditions under which it fails to support the gel spheres.  You are provided with beakers, salt, sugar and water to assist you in your investigations.  You may also have weighted floats called “hydrometers” that can be used in your inquiry.

NOTE:  One of your lab problems for the week asks you to come up with a law that predicts when things will float or sink.  You should use this activity to guide your answer to this question.

An extension: Fluid dynamics & natural convection:

NOTE: This extension would probably need to be done outside of class, possibly as an independent research project.

A liquid or gas (both of which are classified as Afluids@) is said to undergo natural convection when it is heated from below (i.e.: point closest to the source of gravity) and/or cooled from above.  Material from the bottom will then tend to move to the top, and material on the top will tend to move to the bottom.  As simple as it sounds, this actually gets very complicated, and can lead you into research in non-linear systems or chaos.  For this study, describe the conditions for which a fluid will convect, and describe the various patterns of convection that can be formed under various circumstances: temperature differences, fluid depth, container shape, etc.  Orbitz is ideal for this study, since the gel spheres allow you to trace out and follow the patterns of the fluid.  You are also supplied with a heat source, thermometer, and beakers.