### Preparation

Have the Worksheet available for students to look at and describe what would happen for each jar in the four pictures

### Activity

Describe what will happen for each baby food jar in each of the four pictures if it were held under water in those positions.

Describe what you believe would happen for the jar lid system if it was held under water in any position. The four positions and all positions between them.

### Range of student results

##### Water will enter through the holes.
• Water will enter because the jar is being twisted and rotated.
• The water pressure is greater than the air pressure so the water will push the air out.
• The water pressure is greater than the air pressure and therefore will push the air out.
• A vacuum will be created with the release of air from one hole and the water will be sucked into the jar through the other hole.
• Water will enter when you push the jar down because pushing it down increases the pressure in the jar causing the air to escape leaving room in the jar for water to enter.
• Pushing the jar down causes pressure to be released through the jar holes causing bubbles to form and water to fill the jar.
• Pushing the jar down into the water will force water into the jar.
• Pressure is built up causing bubbles to form and then water will start to enter.
• If the jar is held under water with the holes on top water will go into the jar and completely fill it, if it's held under long enough.
• The air will push against the water causing it to move out of its way (and bubble to the surface) of the jar on its side.
• There would be a little bit of water because of the twisting and turning.
• The longer the jar is under water the more water that would enter. If it would be left in overnight there would be more.
• Having a hole on each side helps with pressure being released equally.
• Bubbles will come from the two holes as the water pushes the air out of the jar.
• When one hole is out of the water and the other is in the water.
##### Water will not enter.
• Because it is air tight.
• The jar will float with the lid up so no water will go in.
• The holes are too small to let in the water. The holes are too small to allow the molecules of water to fit through.
• The holes will create an air pocket and not permit water to flow into the jar.
• The pressure from inside the jar is too forceful to let the water in. The air pressure will not allow the water into the jar. The air pressure goes out through the holes keeping the water out. Air pressure will keep the water out. The air pressure is stronger than the water pressure. The air inside is stronger than the water. The air takes up the space and blocks the entrance of the water. Air takes up space and the water will not enter since the air is taking all the space.
• The air will push against the water causing it to move out of its way (allowing it to stay inside the inverted jar).
• If the jar is on its side some air will escape, but not enough to let any water in the jar.
• There is not enough pressure to push the water through the holes.
• The pressure of pushing the jar into or around in the water will push some water into the jar.
• As the jar is pulled out of the water the water will be sucked out because more water is being displaced over a bigger area and the jar will come out of the water with out any water inside.
##### Water will enter depending on the position of the holes.
• Water will enter if one hole is positioned above the other. If the holes are at equal levels the air will be trapped.
• When the jar is pushed in up side down there is more pressure on it and the water will not go in. When the jar is pushed in another way there is less pressure and the water will go in.
• Water enters the bottom hole because there is more pressure on the bottom than on the top.
• If both holes are at the same depth the pressure is the same and no water will enter.
• If the bottle traps the air it occupies the space so that the water cannot enter, if the air can exit through one hole, the water will enter through the other.