This video show us that the bottom of a dropped slinky hovers dramatically in the air. Through this situation some physicists provided new insight into this phenomenon. Shimon Kolkowiz who is a physics graduate student at Harvard University in Cambridge said, “When we hold one end of a Slinky, letting it hang down and then drop it, it turns out the bottom stays suspended, levitating in air for some period in time.” Also he calculated that the bottom of this metal slinky would remain suspended for approximately three-tenths of a second. As a result from this video, the Slinky stretches out, quickly reaching a condition(equilibrium). In witch the downward force of gravity is balanced by the upward tension of the coils above it. When the top of the Slinky collapses, the coils slam into each other. The weaker gravitational field wouldn’t stretch the slinky as much, so the spring would compress more near by the bottom when dropped, it takes some 0.3 seconds to get there. Kolkowiz found out the Slinky’s center of mass, but is always located in between the top and bottom of the toy. So there is no violation of any of Newton’s laws or Galileo’s observations about falling objects. I was interested in this video because if was right after we learned about Newton’s law.
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