Water in cup...upsidedown!

For my mini project i decided to defy gravity with a cool chemistry trick. In this chemistry trick you fill a cup of water you put a piece of cardboard on the bottom then you flip it and the cardboard should stay in place with the water still in the cup. Sounds cool huh well this is what you will need to try this trick out for yourself.

Materials needed:

~ you need a glass of water filled to the top
~ A piece of cardboard, big enough to cover the entire lid of the cup





How to do this trick:
1. You wil need to fill the cup with water to the top
2. You place the piece of cardboard over the rim of the cup
3. make sure no air bublles are in the cup
4. hold the cardboard to the cup sturdily
5.flip the cup upside down
6. remove your hand quickly from the cardboard
Science:
Early I said that this was a chemistry trick the reason why this is a chemistry trick is becuase it shows difference in air pressure. This trick would not be possible with out the difference of air pressure in the cup and the air pressure outside the cup. The reason why the cardboard is able to stay in place while the water in the cup is pushing down on it is because the air pressure out side the cup is higher than the air pressure inside the cup.

Photo credits: Nicole Ho :)