Make a Diver

Make a Diver

Friday, 9th January 2009

Teacher made a diver out of marla, and connected him to a pen cap with a paper clip and an elastic band.First of all we tried to get a marla diver to float without any air tank. It doesn’t. Marla sinks when it is in a ball.

We tried to get the diver to sink and then float again. We did this by shaking the bottle up and down, side to side, forwards and backwards. We tried tapping the diver too. The diver stayed floating.We tried turning the bottle upside down and back again. The diver sank but wouldn’t float again. The same happened when we rolled the bottle.

We discovered that we can get the diver to sink by squeezing the bottle, and we can make him surface again by letting go. This is because the diver floats when the pen cap is full of air but he sinks when the air in the cap is compressed (from the squeezing) and the cap fills with water. Water in the lid is too heavy to keep the diver floating.We made our own divers. Teacher tried them out in a big cup before putting them in a big bottle. They worked really well.