Problem A. Inconspicuous Bottle
Put a lit candle behind a bottle. If you blow on the bottle from the opposite side, the candle may go out, as if the bottle
was not there at all. Explain the phenomenon.
Problem B. Sweet Mirage
Fata Morgana is the name given to a particular form of mirage. A similar effect can be produced by shining a laser
through a fluid with a refractive index gradient. Investigate the phenomenon.
Problem C. Conducting Lines
A line drawn with a pencil on paper can be electrically conducting. Investigate the characteristics of the conducting line.
Problem D. Falling Tower
Identical discs are stacked one on top of another to form a freestanding tower. The bottom disc can be removed by
applying a sudden horizontal force such that the rest of the tower will drop down onto the surface and the tower
remains standing. Investigate the phenomenon and determine the conditions that allow the tower to remain standing.
Problem E. Playing Card
A standard playing card can travel a very long distance provided that spin is imparted as it is thrown. Investigate the
parameters that affect the distance and the trajectory.
Problem F. Swing Sound Tube
A Sound Tube is a toy, consisting of a corrugated plastic tube, that you can spin around to produce sounds. Study the
characteristics of the sounds produced by such toys, and how they are affected by the relevant parameters.
Problem G. Saxon Bowl
A bowl with a hole in its base will sink when placed in water. The Saxons used this device for timing purposes. Investigate
the parameters that determine the time of sinking.
Problem H. Magnetic Levitation
Under certain circumstances, the “flea” of a magnetic stirrer can rise up and levitate stably in a viscous fluid during
stirring. Investigate the origins of the dynamic stabilization of the “flea” and how it depends on the relevant parameters.
Problem I. Friction Oscillator
A massive object is placed onto two identical parallel horizontal cylinders. The two cylinders each rotate with the same
angular velocity, but in opposite directions. Investigate how the motion of the object on the cylinders depends on the
Problem J. Nitinol Engine
Place a nitinol wire loop around two pulleys with their axes located at some distance from each other. If one of the
pulleys is immersed into hot water, the wire tends to straighten, causing a rotation of the pulleys. Investigate the
properties of such an engine.
Problem Selection Committee: Dr. David Bailey, Ryan Lin, Marisca Vanderkamp