What’s happening here?
It looks like the water in the cup is magic! Gravity is pulling the water down but it is also pulling the cup down.
While the water is falling, the cup is falling too – catching the water.
What keeps the cup and water moving in a nice circular path is the string. That is called the centripetal force. Be careful though – if the cup stops, the water will fall out!
This is what happens when you are on a roller-coaster – it’s not the seatbelt that is holding you in place but the centripetal force! (I wouldn’t recommend going on one without a seatbelt though!)