Hover Disk--Interaction Diagrams

Purpose: The purpose of this lab was to test motion without the force of friction. We used a hover disk because it floats on a pocket of air, essentially allowing it to glide on a frictionless surface. We used Newton's 3 Laws to answer the Big Question, "What gives rise to a change in motion?" This lab focused on the different forces being applied to an object--force pairs. This lab is summed up in Newton's Third Law.

How?: In this lab, the object we applied force to was the hover disc. First, we turned on the hover disc (removing friction) and pushed it across the floor to the other person. Then we repeated this with the hover disc off, which added the element of friction. After completing these motions, we looked at the interaction diagrams and filled in arrows to each object which represented the type of force being used.

Conclusion--Interaction Diagrams: As you can see in the two diagrams below, the Force of Gravity (pink) and Normal Force (purple) are ALWAYS present between the earth, the two people, and the hover disc. The Normal Force is only present between the person and the hover disc when they are in contact. Also, notice that once the hover disc was turned off, the Force of Friction (blue) is now added between the hover disc and the earth.

Real World: An example of this lab would be comparing ice skating to walking. When we walk, the Force of Friction is present between us and the ground (hover disc off). This force enables us to keep a steady pace and firm footing on the ground, because without it, we would glide on forever instead of walking. However, ice skating is a little different. Since ice skaters are on blades as well as a slick ice surface, there is less friction between the person and the ice, enabling them to glide smoothly over the surface.