X-ZYlo
Presenter
Andy Jackson, Harrisonburg City Schools, ajackson@harrisonburg.k12.va.us.
Va. SOL:
PH.1
 PH 1 The student will plan and conduct investigations using experimental design and product design processes. Key concepts include a) the components of a system are defined; b) instruments are selected and used to extend observations and measurements; c) information is recorded and presented in an organized format; d) the limitations of the experimental apparatus and design are recognized; e) the limitations of measured quantities are recognized through the appropriate use of significant figures or error ranges; f) models and simulations are used to visualize and explain phenomena, to make predictions from hypotheses, and to interpret data; and PH.3 The student will investigate and demonstrate an understanding of the nature of science, scientific reasoning, and logic. Key concepts include a) analysis of scientific sources to develop and refine research hypotheses; b) analysis of how science explains and predicts relationships; c) evaluation of evidence for scientific theories; d) examination of how new discoveries result in modification of existing theories or establishment of new paradigms; and e) construction and defense of a scientific viewpoint. PH.5 The student will investigate and understand the interrelationships among mass, distance, force, and time through mathematical and experimental processes. Key concepts include a) linear motion; b) uniform circular motion; c) projectile motion; d) Newton’s laws of motion; e) gravitation; National Standards Motion and Forces Objects change their motion only when a net force is applied. Laws of motion are used to calculate precisely the effects of forces on the motion of objects. The magnitude of the change in motion can be calculated using the relationship F = ma, which is independent of the nature of the force. Whenever one object exerts force on another, a force equal in magnitude and opposite in direction is exerted on the first object. Gravitation is a universal force that each mass exerts on any other mass. The strength of the gravitational attractive force between two masses is proportional to the masses and inversely proportional to the square of the distance between them.
Topic and Concept
Experimental design, data collection, center of mass, center of pressure, angular momentum, analysis of scientific source, Bernoulli principle, Torque, technical writing
Materials
• 1 XzyLo
• Paper, masking tape, duct tape, transparencies, soda bottles, scissors, exacto knife
• balance
• rulers
• Physics text and internet

The XzyLo can be thrown at high speeds and has hard thin surfaces that can injure people and damage property. Caution should be exercised with regard to what is down range of a throw.

Presentation
The X-zyLo is a commercial toy available for less than \$10. It is thrown more or less like a football with a spiral and travels a rather amazing distance in a nice straight path once you get used to throwing it. The manufacturer claims “X-zyLo’s world record throw is 218 yards or 655 feet!! Nothing so light has ever been thrown so far!!!” and also claims “Not even NASA can explain how if flies!!!” Demonstrate how well the X-zyLo flies and then challenge the students to investigate and understand why it flies so well. Provide them with the “science lesson” provided by X-zyLo and challenge them to “attack” it and re-write it more clearly and more correctly.
How the Physics Is Demontrated
There are several basic important points about the X-zyLo’s flight that are fairly easily comprehended even though they are explained poorly in the official science lessons produced. These points are center of mass, center of pressure, and gyroscopic stability. Less easily understood, but still within reach is precession. Bernoulli’s principle is easy to understand and is presented moderately well in the paper, but there are “a miracle occurs here” gaps in using it to explain how the X-zyLo utilizes Bernoulli’s principle to achieve lift. And the final analysis of how it flies so well may be out of reach for HS physics …. But who knows!

X-zyLo – the amazing flying gyroscope!! What makes it fly so well? What features of its construction are essential to its great flight?

1. Observe the X-zyLo at rest and in flight. Record your observations.
2. Read the paper that purports to explain the physics of how the X-zyLo flies.
3. Build an X-zyLo and choose a variable to examine and test. Does this variable affect the X-zyLo’s performance? Is this variable related to a feature discussed in the explanation paper? If so how?  Collect data and write up your conclusions regarding the variable you chose to test.
4. Open the word document of the explanation paper. Edit and re-write the paper so the physics is better and the writing is clearer. Use “track changes” so I can see how you changed the paper.

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