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HNQ
10:51 AM
2
Q: Understand total spin in 2 cases

ZhengrongI'm a little bit confused with how to understand the relationships between spin angular momentum (S), orbital angular momentum (L), and the total angular momentum (J) by visualizing those quantities. Classically, if we consider the motion of the Earth, I think S is its rotation, L would be its re...

 
 
6 hours later…
HNQ
5:07 PM
2
Q: Can a Styrofoam box fall back into the moving van?

Krishnanand JI just came across this video. A styrofoam box falls out of a moving van, bounces off the road and lands back in the van. How can the box land back so precisely inside the van?! Usually I would consider these type of videos as bogus. But the fact that the box is very light and that I have seen ...

 

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