 Photo by Donald Collins
Feb. 16, 2003 |
| As the rain collected and froze on this rapidly rotating windmill, the centrifugal action forced the water outward in all directions. As the water drops froze it left icicles radiating outward. Was this "Centrifugal force"? Newtonian physics states that centrifugal force does not pull outward on the spinning objects. The spinning objects are pulled inward by the centripetal force to make them go around a circle. "Centrifugal force" is the force the rotating objects exert on the center of the circle. The water drops and icicles are pulling outward on the rim of the rotating wheel. Sound complicated? How do we explain this simple phenomenon without violating Newtonian physics? |
Paradox Below. Photo by Vicki Collins
Feb. 23, 2003 |
| Paradox: If we watch a wet wheel spinning fast, the water drops fly off tangentially as the photo of the sanding disk shows. How do we reconcile the physics of water leaving the wheel tangentially and the radial icicles on the windmill that was spinning fast in the freezing rain. The explanation will be left as a "contest" and appear in this space next week, along with the winning explanation. Students and faculty may submit their explanations on paper to Donald Collins, Spidel 205 before Friday noon, Feb. 28, 2003. The winner will be selected at among the "thousands" of correct answers expected, so submit your winning explanation on paper (no e-mail) to Donald Collins, Spidel 205. |