Yes, sure its fun to see a lady spin around like that, but I had one of my friends ask me - “Where do you even use this mate?”
Here’s one application that I know very well off.
If you have ever seen a rocket launch, you might know that sometimes the rockets are given a spin while launching. This is known as spin stabilization.
Basically, the rotational inertia of the rotating body will stabilize the rocket against any disturbances and help maintain its intended heading.
The same principle is used in rifling of firearms as well. **
Okay, now there is the question how to “De-spin” the rocket:
Well, you do what the lady does: stretch out your arms and you will slow down !
The rocket has weights connected to a cable that stretch out and almost immediately the rocket slows down. This maneuver is known as the YoYo DeSpin. ( Damn good name ! )
All thanks to the conservation of angular momentum !
Have a good one !
* Another method to stabilization : 3-axis stabilization