More experiments with air

We made fantastic hovercrafts using old CDs, water bottle tops, balloons and blue tack.
We love the way the hovercrafts float on a layer of air to move.

We were fascinated by this next air experiment. When you put tissue into a cup, then put the cup into a bowl of water, the tissue inside the cup stays dry. Why? The tissue stays dry because the air in the cup does not allow water into the cup even if it is turned up-side down in the water. We used blue tissue at first because it is easy to see whether the tissue is wet or dry. Next we used coloured water and white tissue because if the tissue stayed white we knew it also had stayed dry. We are definitely going to try this experiment at home!