Wingardium Leviostraw

 

The ability to make things float or levitate is something that many people wish they would be able to do. A great example of this is when you use a straw to hold liquid inside of it by covering one side with your finger. The liquid inside the straw doesn't fall out. Instead it appears to just levitate in mid air inside the straw. I always thought to myself why is it that this happens? The reason is that the liquid is kept
in the straw by air pressure, the pressure below the finger inside the straw pushes up at a higher pressure than the air can above your finger because it prevents the air from releasing pressure on the liquid from above. The air pressure traps the liquid inside forcing it to hold inside the straw.

-Alex Gallo