@testandtutor: What determines the ball sinks or floats? #thinking #physics #science #scienceismagic #education

HowlingUlf 🇸🇪 :

it's a matter of pressure, right? there is pressure from the water pressing the ping pong ball downwards towards the opening of the bottle where there is only normal air pressure. then you add the second ball which is floating in the water since it's lighter than water. I don't know if I understand what the problem is but did you expect the second bowl to sink in the water or did you expect the first ball to disregard the pressure of the water and float when you poor the water on top of it?