Question

1. If you hold a glass of wine, satellite/planet model up above your head and release it, what will happen? Explain why. Does it happen to them in the video?If not, try to explain why. ( FROM THE VIDEO : I can create a centripetal force greater than the force of gravity and keep the liquid in the wine glass. )
2. https://www.youtube.com/watch?v=FM1Y6tROWEo

Answer 1

If you hold any object up above your head and release it, it will simply fall down.

This is because the only vertical force experienced by the object is gravitational force and it acts downward. So, acceleration is downward.Also, initial velocity is 0. So, the object will fall vertically downward, with increasing speed.

It does not happen in the video because the object experiences 2 forces: i) gravitational which always acts vertically downward, ii) Normal reaction, which acts along the center of the circular trajectory. Also, initially, the object is moving tangentially. The 2 forces provide the necessary centripetal force (if the object has enough speed) to keep the object in a circular trajectory and hence , the object does not fall down vertically.