Cartesian Diver

Lizzy‚ GA | Cartesian Diver
When I squeezed the bottle‚ the straw floated up. When I squeezed it again‚ it came down.

Ji ‚ HI | Cartesian Diver
My results were the when I squeezed the bottle‚ the diver sank all the way to the bottom. But when I didn't squeeze the bottle‚ it would float! It was AWESOME!

chloe | Cartesian Diver
it exploded

Vincent‚ MD | Cartesian Diver
Because when you sqeeze the water pushes the diver up.

satvika‚ DE | Cartesian Diver
THE WATER GOES IN THE BOTTLE

Grace‚ WA | Cartesian Diver
I think the water has more effect to the clay. So the air bubble inside the diver shrinks.

yin‚ MA | Cartesian Diver
when i squeeze the bottle it exploded.

carson‚ SC | Cartesian Diver
the air bubble inside the diver shrinks

Kaleigh‚ CA | Cartesian Diver
i tried this and it didnt work!!!!

debi | Cartesian Diver
i can't get the diver to sink; any help?

Andrew, VA | Cartesian Diver
I'm not sure the explanation for the Cartesian diver is entirely correct. The diver sinks not because the air in the capsule is compressed, but because the water displaced decreases. Water is denser than air, so the pen top becomes less buoyant and sinks. Meanwhile, the weight of the trapped air, compressed or not, is constant.

DragonflyTV | Cartesian Diver
You are correct that water is more dense than air, and you are correct that the air inside the cap displaces less water when compressed. It's also true that the weight (I think you mean to say "mass") of the trapped air is constant, whether compressed or not. However, as the explanation indicates, compressing the air on the cap does increase its *density*, but not its mass. This is simply a correlated fact to the statement that the cap is less buoyant.