======Centripetal Force Marble======


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**Alternative titles:** Marble Gravitron
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====Summary====                   
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====Procedure====  
  - Hold a wine glass (or any oval-shaped glass) upright by its base.  
  - Drop a marble inside the glass.  
  - Rotate the glass in a circular motion so the marble rolls around the inner surface.  
  - Gradually tilt the glass sideways and then upside down while maintaining the marble’s circular motion.  
  - (Optional) Place the marble in your palm and use the inverted spinning glass to scoop it up, getting it moving inside the glass.



====Links==== 
Science minute: Exploring centripetal force - 9NEWS: 
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📄 Marble Gravitron - Steve Spangler: [[https://stevespangler.com/experiments/marble-gravitron-2/]]\\

====Variations====
  * Try different glass shapes to see how the path of the marble changes.  
  * Spin marbles of different sizes or weights and compare how long they stay in motion.  
  * Use two marbles at once to observe their interaction while spinning.



====Safety Precautions====
  * Adult supervision is required, especially when using fragile glass.  
  * Perform the demonstration over a soft surface like carpet to prevent breakage if the glass or marble is dropped.  
  * Keep marbles away from small children due to choking hazard.




====Questions to Consider====
  * What force keeps the marble pressed against the inside of the glass? (Centripetal force from the glass walls.)  
  * Why doesn’t the marble fall when the glass is upside down? (The marble’s inertia and the centripetal force are stronger than gravity while spinning fast.)  
  * What happens when the glass slows down? (The marble loses centripetal force, gravity takes over, and it falls.)  
  * How is this similar to the amusement park Gravitron ride? (Both rely on circular motion and centripetal force to hold objects or people against the walls.)